CAcert CPS and CP

Name: CPS COD6
Creation Date : 20060726, drafted at 20091108
Editor: NN
Status: POLICY p20140731
Licence: CC-by-sa+DRP


1.1. Overview

This document is the Certification Practice Statement (CPS) of CAcert, the Community Certification Authority (CA). It describes rules and procedures used by CAcert for operating its CA, and applies to all CAcert PKI Participants, including Assurers, Members, and CAcert itself.

1.2. Document name and identification

This document is the Certification Practice Statement (CPS) of CAcert. The CPS also fulfills the role of the Certificate Policy (CP) for each class of certificate.

The CPS is an authoritive document, and rules other documents except where explicitly deferred to. See also 1.5.1 Organisation Administering the Document.

1.3. PKI participants

The CA is legally operated by CAcert Incorporated, an Association registered in 2002 in New South Wales, Australia, on behalf of the wider Community of Members of CAcert. The Association details are at the CAcert wiki.

CAcert is a Community formed of Members who agree to the CAcert Community Agreement. The CA is technically operated by the Community, under the direction of the Board of CAcert Incorporated. (The Members of the Community are not to be confused with the Association Members, which latter are not referred to anywhere in this CPS.)

1.3.1. Certification authorities

CAcert does not issue certificates to external intermediate CAs under the present CPS.

1.3.2. Registration authorities

Registration Authorities (RAs) are controlled under Assurance Policy (COD13).

1.3.3. Subscribers

CAcert issues certificates to Members only. Such Members then become Subscribers.

1.3.4. Relying parties

A relying party is a Member, having agreed to the CAcert Community Agreement (COD9), who, in the act of using a CAcert certificate, makes a decision on the basis of that certificate.

1.3.5. Other participants

Member. Membership of the Community is as defined in the COD9. Only Members may RELY or may become Subscribers. Membership is free.

Arbitrator. A senior and experienced Member of the CAcert Community who resolves disputes between Members, including ones of certificate reliance, under Dispute Resolution Policy (COD7).

Vendor. Software suppliers who integrate the root certificates of CAcert into their software also assume a proxy role of Relying Parties, and are subject to another licence.

Non-Related Persons (NRPs). These are users of browsers and similar software who are unaware of the CAcert certificates they may use, and are unaware of the ramifications of usage. Their relationship with CAcert is described by the Non-related Persons - Disclaimer and Licence (COD4). No other rights nor relationship is implied or offered.

1.4. Certificate usage

CAcert serves as issuer of certificates for individuals, businesses, governments, charities, associations, churches, schools, non-governmental organisations or other groups. CAcert certificates are intended for low-cost community applications especially where volunteers can become Assurers and help CAcert to help the Community.

Types of certificates and their appropriate and corresponding applications are defined in §1.4.1. Prohibited applications are defined in §1.4.2. Specialist uses may be agreed by contract or within a specific environment, as described in §1.4.4. Note also the unreliable applications in §1.4.3 and risks, liabilities and obligations in §9.

Appropriate Certificate uses
General Protocol
TLS web server encryption enables encryption
embedded embedded server authentication mail servers, IM-servers
S/MIME email encryption "digital signatures" employed in S/MIME are not legal / human signatures, but instead enable the encryption mode of S/MIME
TLS client authentication the nodes must be secure
TLS web based signature applications the certificate authenticates only. See §1.4.3.
"Digital Signing" for human signing over documents Only within a wider application and rules such as by separate policy, as agreed by contract, etc. See §1.4.4.
Authenticode, ElfSign, Java Code Signing Signatures on packages are evidence of their Membership and indicative of Identity
OpenPGP Key Signing Signatures on Member Keys are evidence of their Membership and indicative of Identity
X.509 OCSP, Timestamping Only available to CAcert Systems Administrators, as controlled by Security Policy
Table 1.4. Types of Certificate

1.4.1. Appropriate certificate uses

General uses.

1.4.2. Prohibited certificate uses

CAcert certificates are not designed, intended, or authorised for the following applications:

1.4.3. Unreliable Applications

CAcert certificates are not designed nor intended for use in the following applications, and may not be reliable enough for these applications:

1.4.4. Limited certificate uses

By contract or within a specific environment (e.g. internal to a company), CAcert Members are permitted to use Certificates for higher security, customised or experimental applications. Any such usage, however, is limited to such entities and these entities take on the whole responsible for any harm or liability caused by such usage.

Digital signing applications. CAcert client certificates may be used by Assured Members in applications that provide or support the human signing of documents (known here as "digital signing"). This must be part of a wider framework and set of rules. Usage and reliance must be documented either under a separate CAcert digital signing policy or other external regime agreed by the parties.

1.4.5. Roots and Names

Named Certificates. Assured Members may be issued certificates with their verified names in the certificate. In this role, CAcert operates and supports a network of Assurers who verify the identity of the Members. All Names are verified, either by Assurance or another defined method under policy (c.f. Organisations).

Anonymous Certificates. Members can be issued certificates that are anonymous, which is defined as the certificate with no Name included, or a shared name such as "Community Member". These may be considered to be somewhere between Named certificates and self-signed certificates. They have serial numbers in them which is ultimately traceable via dispute to a Member, but reliance is undefined. In this role, CAcert provides the infrastructure, saving the Members from managing a difficult and messy process in order to get manufactured certificates.

Psuedonymous Certificates. Note that CAcert does not currently issue pseudonymous certificates, being those with a name chosen by the Member and not verifiable according to documents.

Advanced Certificates. Members who are as yet unassured are not permitted to create advanced forms such as wildcard or subjectAltName certificates.

Roots. The CAcert root layout is as below. These roots are pending Audit, and will be submitted to vendors via the (Top-level) Root.

Level of Assurance
Members †
Assured Members
Class of Root Anon Name Anon Name Name+Anon
Top level
Signs other CAcert SubRoots only.
† For Members meeting basic checks in §4.2.2
(Reliance is undefined.)
Assured Members only.
Fully intended for reliance.
Assured Organisation Members only.
Fully intended for reliance.
Expiry of Certificates
6 months
24 months
client, server
wildcard, subjectAltName
(Inclusive to the left.)
Table 1.4.5.b Certificate under Audit Roots
Level of Assurance
Assured Members
Class of Root Anonymous Named Anonymous Named
Available for all Members,
reliance is undefined.
Assured Members only.
Intended for Reliance.
Expiry of Certificates
6 months
24 months
Types available
simple only
wildcard, subjectAltName
Table 1.4.5. Certificates under Old Roots - Audit Fail

Old Roots. The old CAcert root layout is as below. These roots are Audit Fail and will only be used where new roots do not serve:

1.5. Policy administration

See 1.2 Document Name and Identification for general scope of this document.

1.5.1. Organization administering the document

This document is administered by the policy group of the CAcert Community under Policy on Policy (COD1).

1.5.2. Contact person

For questions including about this document:

1.5.3. Person determining CPS suitability for the policy

This CPS and all other policy documents are managed by the policy group, which is a group of Members of the Community found at policy forum. See discussion forums above.

1.5.4. CPS approval procedures

CPS is controlled and updated according to the Policy on Policy (COD1) which is part of Configuration-Control Specification (COD2).

In brief, the policy forum prepares and discusses. After a last call, the document moves to DRAFT status for a defined period. If no challenges have been received in the defined period, it moves to POLICY status. The process is modelled after some elements of the RFC process by the IETF.

1.5.5. CPS updates

As per above.

1.6. Definitions and acronyms

Certificate. A certificate is a piece of cryptographic data used to validate certain statements, especially those of identity and membership.

CAcert. CAcert is a Community certificate authority as defined under §1.2 Identification.

Member. Everyone who agrees to the CAcert Community Agreement (COD9). This generally implies having an account registered at CAcert and making use of CAcert's data, programs or services. A Member may be an individual ("natural person") or an organisation (sometimes, "legal person").

Community. The group of Members who agree to the CAcert Community Agreement (COD9) or equivalent agreements.

Unassured Member. A Member who has not yet been Assured.

Subscriber. A Member who requests and receives a certificate.

Assured Member. A Member whose identity has been sufficiently verified by Assurers or other approved methods under Assurance Policy.

Assurer. An Assured Member who is authorised under Assurance Policy to verify the identity of other Members.

Name. As defined in the Assurance Policy (COD13), to describe a name of a Member that is verified by the Assurance process.

Organisation Administrator. ("O-Admin") An Assurer who is authorised to act for an Organisation. The O-Admin is authorised by an organisation to vouch for the identity of other users of the organisation.

Organisation Assurer. An Assurer who is authorised to conduct assurances on organisations.

Non-Related Persons. ("NRPs") are general users of browsers and similar software. The NRPs are generally unaware of CAcert or the certificates that they may use, and are unaware of the ramifications of usage. They are not permitted to RELY, but may USE, under the Non-Related Persons - Disclaimer and Licence (COD4).

Reliance. An industry term referring to the act of making a decision, including taking a risk, which decision is in part or in whole informed or on the basis of the contents of a certificate.

Relying Party. An industry term refering to someone who relies (that is, makes decisions or takes risks) in part or in whole on a certificate.

Subscriber Naming. The term used in this CPS to describe all naming data within a certificate. Approximately similar terms from Industry such as "Subject naming" and "Distinguished Name" are not used here.

Verification. An industry term referring to the act of checking and controlling the accuracy and utility of a single claim.

Validation. An industry term referring to the process of inspecting and verifying the information and subsidiary claims behind a claim.

Usage. The event of allowing a certificate to participate in a protocol, as decided and facilitated by a user's software. Generally, Usage does not require significant input, if any, on the part of the user. This defers all decisions to the user software, thus elevating the software as user's only and complete Validation Authority or Agent.

CAcert Relying Party. CAcert Members who make decisions based in part or in whole on a certificate issued by CAcert. Only CAcert Members are permitted to Rely on CAcert certificates, subject to the CAcert Community Agreement.

Vendors. Non-members who distribute CAcert's root or intermediate certificates in any way, including but not limited to delivering these certificates with their products, e.g. browsers, mailers or servers. Vendors are covered under a separate licence.

Configuration-Control Specification "CCS". The audit criteria that controls this CPS. The CCS is documented in COD2, itself a controlled document under CCS.

CAcert Official Document (COD). Controlled Documents that are part of the CCS.


2.1. Repositories

CAcert operates no repositories in the sense of lookup for non-certificate-related information for the general public.

Under the Assurance Policy (COD13), there are means for Members to search, retrieve and verify certain data about themselves and others.

2.2. Publication of certification information

CAcert publishes:

CAcert does not expressly publish information on issued certificates. However, due to the purpose of certificates, and the essential public nature of Names and email addresses, all information within certificates is presumed to be public and published, once issued and delivered to the Member.

2.3. Time or frequency of publication

Root and Intermediate Certificates and CRLs are made available on issuance.

2.4. Access controls on repositories

No stipulation.


3.1. Naming

3.1.1. Types of names

Client Certificates. The Subscriber Naming consists of:

Individual Server Certificates. The Subscriber Naming consists of:

Certificates for Organisations. In addition to the above, the following applies:

Except for the OU and CN, fields are taken from the Member's account and are as verified by the Organisation Assurance process. Other Subscriber information that is collected and/or retained does not go into the certificate.

3.1.2. Need for names to be meaningful

Each Member's Name (CN= field) is assured under the Assurance Policy (COD13) or subsidiary policies (such as Organisation Assurance Policy). Refer to those documents for meanings and variations.

Anonymous certificates have the same subject field common name. See §1.4.5..

Email addresses are verified according to §4.2.2.

3.1.3. Anonymity or pseudonymity of subscribers

See §1.4.5.

3.1.4. Rules for interpreting various name forms

Interpretation of Names is controlled by the Assurance Policy, is administered by means of the Member's account, and is subject to change by the Arbitrator. Changes to the interpretation by means of Arbitration should be expected as fraud (e.g., phishing) may move too quickly for policies to fully document rules.

3.1.5. Uniqueness of names

Uniqueness of Names within certificates is not guaranteed. Each certificate has a unique serial number which maps to a unique account, and thus maps to a unique Member. See the Assurance Statement within Assurance Policy (COD13).

Domain names and email address can only be registered to one Member.

3.1.6. Recognition, authentication, and role of trademarks

Organisation Assurance Policy (COD11) controls issues such as trademarks where applicable. A trademark can be disputed by filing a dispute. See §9.13.

3.1.7. International Domain Names

Certificates containing International Domain Names, being those containing a ACE prefix (RFC3490 Section 5), will only be issued to domains satisfying one or more of the following conditions:

Email address containing International Domain Names in the domain portion of the email address will also be required to satisfy one of the above conditions.

The following is a list of accepted TLD Registrars:

.ac Registry Policy
.ar Registry Policy
.at Registry Policy (character list)
.biz Registry Policy
.br Registry Policy
.cat Registry Policy
.ch Registry Policy
.cl Registry Policy
.cn Registry Policy (JET Guidelines)
.de Registry Policy
.dk Registry Policy
.es Registry Policy
.fi Registry Policy
.gr Registry Policy
.hu Registry Policy (section 2.1.2)
.info Registry Policy
.io Registry Policy
.ir Registry Policy
.is Registry Policy
.jp Registry Policy
.kr Registry Policy (JET Guidelines)
.li Registry Policy (managed by .ch registry)
.lt Registry Policy (character list)
.museum Registry Policy
.no Registry Policy (section 4)
.org Registry Policy
.pl Registry Policy
.pr Registry Policy
.se Registry Policy (character list)
.sh Registry Policy
.th Registry Policy
.tm Registry Policy
.tw Registry Policy (JET Guidelines)
.vn Registry Policy (character list)

This criteria will apply to the email address and server host name fields for all certificate types.

The CAcert Inc. Board has the authority to decide to add or remove accepted TLD Registrars on this list.

3.2. Initial Identity Verification

Identity verification is controlled by the Assurance Policy (COD13). The reader is refered to the Assurance Policy, the following is representative and brief only.

3.2.1. Method to prove possession of private key

CAcert uses industry-standard techniques to prove the possession of the private key.

For X.509 server certificates, the stale digital signature of the CSR is verified. For X.509 client certificates for "Netscape" browsers, SPKAC uses a challenge-response protocol to check the private key dynamically. For X.509 client certificates for "explorer" browsers, ActiveX uses a challenge-response protocol to check the private key dynamically.

3.2.2. Authentication of Individual Identity

Agreement. An Internet user becomes a Member by agreeing to the CAcert Community Agreement (COD9) and registering an account on the online website. During the registration process Members are asked to supply information about themselves:

The online account establishes the method of authentication for all service requests such as certificates.

Assurance. Each Member is assured according to Assurance Policy (COD13).

Certificates. Based on the total number of Assurance Points that a Member (Name) has, the Member can get different levels of certificates. See §1.4.5. See Table 3.2.b. When Members have 50 or more points, they become Assured Members and may then request certificates that state their Assured Name(s).

Assurance Points Level Service Comments
0 Unassured Member Anonymous Certificates with no Name, under Class 1 Root. Limited to 6 months expiry.
1-49 Unassured Member Anonymous Certificates with no Name under Member SubRoot. Limited to 6 months expiry.
50-99 Assured Member Verified Certificates with Verified Name for S/MIME, web servers, "digital signing." Expiry after 24 months is available.
100++ Assurer Code-signing Can create Code-signing certificates
Table 3.2.b - How Assurance Points are used in Certificates

3.2.3. Authentication of organization identity

Verification of organisations is delegated by the Assurance Policy to the Organisation Assurance Policy (COD11). The reader is refered to the Organisation Assurance Policy, the following is representative and brief only.

Organisations present special challenges. The Assurance process for Organisations is intended to permit the organisational Name to appear in certificates. The process relies heavily on the Individual process described above.

Organisation Assurance achieves the standard stated in the OAP, briefly presented here:

  1. the organisation exists,
  2. the organisation name is correct and consistent,
  3. signing rights: requestor can sign on behalf of the organisation, and
  4. the organisation has agreed to the terms of the CAcert Community Agreement (COD9), and is therefore subject to Arbitration.

3.2.4. Non-verified subscriber information

All information in the certificate is verified, see Relying Party Statement, §4.5.2.

3.2.5. Validation of authority

The authorisation to obtain a certificate is established as follows:

Addresses. The member claims authority over a domain or email address when adding the address, §4.1.2. (Control is tested by means described in §4.2.2.)

Individuals. The authority to participate as a Member is established by the CAcert Community Agreement (COD9). Assurances are requested by means of the signed CAP form.

Organisations. The authority for Organisation Assurance is established in the COAP form, as signed by an authorised representative of the organisation. The authority for the Organisation Administrator (O-Admin) is also established on the COAP form. See Organisation Assurance Policy.

3.2.6. Criteria for interoperation

CAcert does not currently issue certificates to subordinate CAs or other PKIs. Other CAs may become Members, and are then subject to the same reliance provisions as all Members.

3.3. Re-key Requests

Via the Member's account.

3.4. Revocations Requests

Via the Member's account. In the event that the Member has lost the password, or similar, the Member emails the support team who either work through the lost-password questions process or file a dispute.


The general life-cycle for a new certificate for an Individual Member is:

  1. Member adds claim to an address (domain/email).
  2. System probes address for control.
  3. Member creates key pair.
  4. Member submits CSR with desired options (Anonymous Certificate, SSO, Root Certificate) .
  5. System validates and accepts CSR based on known information: claims, assurance, controls, technicalities.
  6. System signs certificate.
  7. System makes signed certificate available to Member.
  8. Member accepts certificate.

(Some steps are not applicable, such as anonymous certificates.)

4.1. Certificate Application

4.1.1. Who can submit a certificate application

Members may submit certificate applications. On issuance of certificates, Members become Subscribers.

4.1.2. Adding Addresses

The Member can claim ownership or authorised control of a domain or email address on the online system. This is a necessary step towards issuing a certificate. There are these controls:

4.1.3. Preparing CSR

Members generate their own key-pairs. The CAcert Community Agreement (COD9) obliges the Member as responsible for security. See CCA2.5, §9.6.

The Certificate Signing Request (CSR) is prepared by the Member for presentation to the automated system.

4.2. Certificate application processing

The CA's certificate application process is completely automated. Requests, approvals and rejections are handled by the website system. Each application should be processed in less than a minute.

Where certificates are requested for more than one purpose, the requirements for each purpose must be fulfilled.

4.2.1. Authentication

The Member logs in to her account on the CAcert website and thereby authenticates herself with username and passphrase or with her CAcert client-side digital certificate.

4.2.2. Verifying Control

In principle, at least two controls are placed on each address.

Email-Ping. Email addresses are verified by means of an Email-Ping test:

Email Control. Email addresses for client certificates are verified by passing the following checks:

  1. An Email-ping test is done on the email address.
  2. The Member must have signed a CAP form or equivalent, and been awarded at least one Assurance point.

Domain Control. Domains addresses for server certificates are verified by passing two of the following checks:

  1. An Email-ping test is done on an email address chosen from whois or interpolated from the domain name.
  2. The system generates a cookie which is then placed in DNS by the Member.
  3. The system generates a cookie which is then placed in HTTP headers or a text file on the website by the Member.
  4. Statement by at least 2 Assurers about ownership/control of the domain name.
  5. The system generates a cookie which is then placed in whois registry information by the Member.


4.2.3. Options Available

The Member has options available:

4.2.4. Client Certificate Procedures

For an individual client certificate, the following is required.

4.2.5. Server Certificate Procedures

For a server certificate, the following is required:

4.2.6. Code-signing Certificate Procedures

Code-signing certificates are made available to Assurers only. They are processed in a similar manner to client certificates.

4.2.7. Organisation Domain Verification

Organisation Domains are handled under the Organisation Assurance Policy and the Organisation Handbook.

4.3. Certificate issuance

4.3.1. CA actions during certificate issuance

Key Sizes. Members may request keys of any size permitted by the key algorithm. Many older hardware devices require small keys.

Algorithms. CAcert currently only supports the RSA algorithm for X.509 keys. X.509 signing uses the SHA-1 message digest algorithm. OpenPGP Signing uses RSA signing over RSA and DSA keys.

Process for Certificates: All details in each certificate are verified by the website issuance system. Issuance is based on a 'template' system that selects profiles for certificate lifetime, size, algorithm.

  1. The CSR is verified.
  2. Data is extracted from CSR and verified:
  3. Certificate is generated from template.
  4. Data is copied from CSR.
  5. Certificate is signed.
  6. Certificate is stored as well as mailed.

Process for OpenPGP key signatures: All details in each Sub-ID are verified by the website issuance system. Issuance is based on the configuration that selects the profile for signature lifetime, size, algorithm following the process:

  1. The public key is verified.
  2. Data is extracted from the key and verified (Name, Emails). Only the combinations of data in Table 4.3.1 are permitted.
  3. OpenPGP Key Signature is generated.
  4. Key Signature is applied to the key.
  5. The signed key is stored as well as mailed.

Verified Name Unverified Name
Empty Name
Verified email
Unverified email
Empty email

Table 4.3.1. Permitted Data in Signed OpenPgp Keys

4.3.2. Notification to subscriber by the CA of issuance of certificate

Once signed, the certificate is made available via the Member's account, and emailed to the Member. It is also archived internally.

4.4. Certificate acceptance

4.4.1. Conduct constituting certificate acceptance

There is no need for the Member to explicitly accept the certificate. In case the Member does not accept the certificate, the certificate has to be revoked and made again.

4.4.2. Publication of the certificate by the CA

CAcert does not currently publish the issued certificates in any repository. In the event that CAcert will run a repository, the publication of certificates and signatures there will be at the Member's options. However note that certificates that are issued and delivered to the Member are presumed to be published. See §2.2.

4.4.3. Notification of certificate issuance by the CA to other entities

There are no external entities that are notified about issued certificates.

4.5. Key pair and certificate usage

All Members (subscribers and relying parties) are obliged according to the CAcert Community Agreement (COD9) See especially 2.3 through 2.5.

4.5.1. Subscriber Usage and Responsibilities

Subscribers should use keys only for their proper purpose, as indicated by the certificate, or by wider agreement with others.

4.5.2. Relying Party Usage and Responsibilities

Relying parties (Members) may rely on the following.

Relying Party Statement

Certificates are issued to Members only.

All information in a certificate is verified.

The following notes are in addition to the Relying Party Statement, and can be seen as limitations on it.

4.5.2.a Methods of Verification

The term Verification as used in the Relying Party Statement means one of

Type How Authority remarks
Assurance under CAcert Assurance Programme (CAP) Assurance Policy only information assured to 50 points under CAP is placed in the certificate
Evaluation under automated domain and email checks this CPS see §4.2.2
Controlled programs or "profiles" that check the information within the CSR this CPS see §7.1
4.5.2.b Who may rely

Members may rely. Relying parties are Members, and as such are bound by this CPS and the CAcert Community Agreement (COD9). The licence and permission to rely is not assignable.

Suppliers of Software. CAcert roots may be distributed in software, and those providers may enter into agreement with CAcert by means of the Third Party Vendor - Disclaimer and Licence (wip). This licence brings the supplier in to the Community to the extent that they agree to dispute resolution within CAcert's forum.

NRPs may not rely. If not related to CAcert by means of an agreement that binds the parties to dispute resolution within CAcert's forum, a person is a Non-Related-Person (NRP). An NRP is not permitted to rely and is not a Relying Party. For more details, see the NRP - Disclaimer and Licence (COD4).

4.5.2.c The Act of Reliance

Decision making. Reliance means taking a decision that is in part or in whole based on the information in the certificate. A Relying Party may incorporate the information in the certificate, and the implied information such as Membership, into her decision-making. In making a decision, a Relying Party should also:

Examining the Certificate. A Relying Party must make her own decision in using each certificate. She must examine the certificate, a process called validation. Certificate-related information includes, but is not limited to:

Keeping Records. Records should be kept, appropriate to the import of the decision. The certificate should be preserved. This should include sufficient evidence to establish who the parties are (especially, the certificate relied upon), to establish the transaction in question, and to establish the wider agreement that defines the act.

Wider Protocol. In principle, reliance will be part of a wider protocol (customary method in reaching and preserving agreement) that presents and preserves sufficient of the evidence for dispute resolution under CAcert's forum of Arbitration. The protocol should be agreed amongst the parties, and tuned to the needs. This CPS does not define any such protocol. In the absence of such a protocol, reliance will be weakened; a dispute without sufficient evidence may be dismissed by an Arbitrator.

As Compared to Usage. Reliance goes beyond Usage. The latter is limited to letting the software act as the total and only Validation Authority. When relying, the Member also augments the algorithmic processing of the software with her own checks of the business, technical and certificate aspect.

4.5.2.d Risks and Limitations of Reliance

Roots and Naming. Where the Class 1 root is used, this Subscriber may be a new Member including one with zero points. Where the Name is not provided, this indicates it is not available. In these circumstances, reliance is not defined, and Relying parties should take more care. See Table 4.5.2.

Statements of Reliance for Members
Class of Root
(all Members)
(Assured Members only)
Do not rely.
Relying party must use other methods to check.
Do not rely. Although the named Member has been Assured by CAcert, reliance is not defined with Class 1 root.
(issued for compatibility only).
Do not rely on the Name (being available). The Member has been Assured by CAcert, but reliance is undefined. The Member named in the certificate has been Assured by CAcert.
Table 4.5.2. Statements of Reliance

Software Agent. When relying on a certificate, relying parties should note that your software is responsible for the way it shows you the information in a certificate. If your software agent hides parts of the information, your sole remedy may be to choose another software agent.

Malware. When relying on a certificate, relying parties should note that platforms that are vulnerable to viruses or trojans or other weaknesses may not process any certificates properly and may give deceptive or fraudulent results. It is your responsibility to ensure you are using a platform that is secured according to the needs of the application.

4.5.2.e When something goes wrong

In the event that an issue arises out of the Member's reliance, her sole avenue is to file dispute under DRP. See §9.13. For this purpose, the certificate (and other evidence) should be preserved.

Which person? Members may install certificates for other individuals or in servers, but the Member to whom the certificate is issued remains the responsible person. E.g., under Organisation Assurance, an organisation is issued a certificate for the use by individuals or servers within that organisation, but the Organisation is the responsible person.

Software Agent. If a Member is relying on a CAcert root embedded in the software as supplied by a vendor, the risks, liabilities and obligations of the Member do not automatically transfer to the vendor.

4.6. Certificate renewal

A certificate can be renewed at any time. The procedure of certificate renewal is the same as for the initial certificate issuance.

4.7. Certificate re-key

Certificate "re-keyings" are not offered nor supported. A new certificate with a new key has to be requested and issued instead, and the old one revoked.

4.8. Certificate modification

Certificate "modifications" are not offered nor supported. A new certificate has to be requested and issued instead.

4.9. Certificate revocation and suspension

4.9.1. Circumstances for revocation

Certificates may be revoked under the following circumstances:

  1. As initiated by the Subscriber through her online account.
  2. As initiated in an emergency action by a support team member. Such action will immediately be referred to dispute resolution for ratification.
  3. Under direction from the Arbitrator in a duly ordered ruling from a filed dispute.

These are the only three circumstances under which a revocation occurs.

4.9.2. Who can request revocation

As above.

4.9.3. Procedure for revocation request

The Subscriber logs in to her online account through the website at .

In any other event such as lost passwords or fraud, a dispute should be filed by email at < support AT cacert DOT org >

4.9.4. Revocation request grace period

No stipulation.

4.9.5. Time within which CA must process the revocation request

The revocation automated in the Web Interface for subscribers, and is handled generally in less than a minute.

A filed dispute that requests a revocation should be handled within a five business days, however the Arbitrator has discretion.

4.9.6. Revocation checking requirement for relying parties

Each revoked certificate is recorded in the certificate revocation list (CRL). Relying Parties must check a certificate against the most recent CRL issued, in order to validate the certificate for the intended reliance.

4.9.7. CRL issuance frequency (if applicable)

A new CRL is issued after every certificate revocation.

4.9.8. Maximum latency for CRLs (if applicable)

The maximum latency between revocation and issuance of the CRL is 1 hour.

4.9.9. On-line revocation/status checking availability

OCSP is available at .

4.9.10. On-line revocation checking requirements

Relying parties must check up-to-date status before relying.

4.9.11. Other forms of revocation advertisements available


4.9.12. Special requirements re key compromise

Subscribers are obliged to revoke certificates at the earliest opportunity.

4.9.13. Circumstances for suspension

Suspension of certificates is not available.

4.9.14. Who can request suspension

Not applicable.

4.9.15. Procedure for suspension request

Not applicable.

4.9.16. Limits on suspension period

Not applicable.

4.10. Certificate status services

4.10.1. Operational characteristics

OCSP is available at .

4.10.2. Service availability

OCSP is made available on an experimental basis.

4.10.3. Optional features

No stipulation.

4.11. End of subscription

Certificates include expiry dates.

4.12. Key escrow and recovery

4.12.1. Key escrow and recovery policy and practices

CAcert does not generate nor escrow subscriber keys.

4.12.2. Session key encapsulation and recovery policy and practices

No stipulation.


5.1. Physical controls

Refer to Security Policy (COD8)

5.1.1. Power and air conditioning

Refer to Security Policy 2.1.2 (COD8)

5.1.2. Water exposures

Refer to Security Policy 2.1.4 (COD8)

5.1.3. Fire prevention and protection

Refer to Security Policy 2.1.4 (COD8)

5.1.4. Media storage

Refer to Security Policy 4.3 (COD8)

5.1.5. Waste disposal

No stipulation.

5.1.6. Off-site backup

Refer to Security Policy 4.3 (COD8)

5.2. Procedural controls

5.2.1. Trusted roles

5.2.2. Number of persons required per task

CAcert operates to the principles of four eyes and dual control. All important roles require a minimum of two persons. The people may be tasked to operate with an additional person observing (four eyes), or with two persons controlling (dual control).

5.2.3. Identification and authentication for each role

All important roles are generally required to be assured at least to the level of Assurer, as per AP. Refer to Assurance Policy (COD13).

Technical. Refer to Security Policy 9.1 (COD8).

5.2.4. Roles requiring separation of duties

Roles strive in general for separation of duties, either along the lines of four eyes principle or dual control.

5.3. Personnel controls

5.3.1. Qualifications, experience, and clearance requirements

Role Policy Comments
Assurer COD13 Passes Challenge, Assured to 100 points.
Organisation Assurer COD11 Trained and tested by two supervising OAs.
Technical SM => COD08 Teams responsible for testing.
Arbitrator COD7 Experienced Assurers.
Table 5.3.1. Controls on Roles

5.3.2. Background check procedures

Refer to Security Policy 9.1.3 (COD8).

5.3.3. Training requirements

No stipulation.

5.3.4. Retraining frequency and requirements

No stipulation.

5.3.5. Job rotation frequency and sequence

No stipulation.

5.3.6. Sanctions for unauthorized actions

Any actions that are questionable - whether uncertain or grossly negligent - may be filed as a dispute. The Arbitrator has wide discretion in ruling on loss of points, retraining, or termination of access or status. Refer to DRP.

5.3.7. Independent contractor requirements

No stipulation.

5.3.8. Documentation supplied to personnel

No stipulation.

5.4. Audit logging procedures

Refer to Security Policy 4.2, 5 (COD8).

5.5. Records archival

The standard retention period is 7 years. Once archived, records can only be obtained and verified by means of a filed dispute. Following types of records are archived:

Record Nature Exceptions Documentation
Member username, primary and added addresses, security questions, Date of Birth resigned non-subscribers: 0 years. Security Policy and Privacy Policy
Assurance CAP forms "at least 7 years."
as per subsidiary policies
Assurance Policy 4.5
Organisation Assurance COAP forms as per subsidiary policies Organisation Assurance Policy
certificates and revocations for reliance 7 years after termination this CPS
critical roles background check worksheets under direct Arbitrator control Security Policy 9.1.3
Table 5.5. Documents and Retention

5.6. Key changeover

Refer to Security Policy 9.2 (COD8).

5.7. Compromise and disaster recovery

Refer to Security Policy 5, 6 (COD8). (Refer to §1.4 for limitations to service.)

5.8. CA or RA termination

5.8.1. CA termination

In the event of operational termination, the Roots (including SubRoots) and all private Member information will be secured. The Roots will be handed over to a responsible party for the sole purpose of issuing revocations. Member information will be securely destroyed.

5.8.2. RA termination

When an Assurer desires to voluntarily terminates her responsibilities, she does this by filing a dispute, and following the instructions of the Arbitrator.

In the case of involuntary termination, the process is the same, save for some other party filing the dispute.


6.1. Key Pair Generation and Installation

6.1.1. Key Pair Generation

Subscribers generate their own Key Pairs.

6.1.2. Subscriber Private key security

There is no technical stipulation on how Subscribers generate and keep safe their private keys, however, CCA 2.5 provides for general security obligations. See §9.6.

6.1.3. Public Key Delivery to Certificate Issuer

Members login to their online account. Public Keys are delivered by cut-and-pasting them into the appropriate window. Public Keys are delivered in signed-CSR form for X.509 and in self-signed form for OpenPGP.

6.1.4. CA Public Key delivery to Relying Parties

The CA root certificates are distributed by these means:

6.1.5. Key sizes

No limitation is placed on Subscriber key sizes.

CAcert X.509 root and intermediate keys are currently 4096 bits. X.509 roots use RSA and sign with the SHA-1 message digest algorithm. See §4.3.1.

OpenPGP Signing uses both RSA and DSA (1024 bits).

CAcert adds larger keys and hashes in line with general cryptographic trends, and as supported by major software suppliers.

6.1.6. Public key parameters generation and quality checking

No stipulation.

6.1.7. Key Usage Purposes

CAcert roots are general purpose. Each root key may sign all of the general purposes - client, server, code.

The website controls the usage purposes that may be signed. This is effected by means of the 'template' system.

6.2. Private Key Protection and Cryptographic Module Engineering Controls

6.2.1. Cryptographic module standards and controls

SubRoot keys are stored on a single machine which acts as a Cryptographic Module, or signing server. It operates a single daemon for signing only. The signing server has these security features:

See §5. and the Security Policy 9.3.1.

(Hardware-based, commercial and standards-based cryptographic modules have been tried and tested, and similar have been tested, but have been found wanting, e.g., for short key lengths and power restrictions.)

6.3. Other aspects of key pair management

6.3.1. Public key archival

Subscriber certificates, including public keys, are stored in the database backing the online system. They are not made available in a public- or subscriber-accessible archive, see §2. They are backed-up by CAcert's normal backup procedure, but their availability is a subscriber responsibility.

6.3.2. Certificate operational periods and key pair usage periods

The operational period of a certificate and its key pair depends on the Assurance status of the Member, see §1.4.5 and Assurance Policy (COD13).

The CAcert (top-level) Root certificate has a 30 year expiry. SubRoots have 10 years, and are to be rolled over more quickly. The keysize of the root certificates are chosen in order to ensure an optimum security to CAcert Members based on current recommendations from the cryptographic community and maximum limits in generally available software. At time of writing this is 4096 bits.

6.4. Activation data

No stipulation.

6.5. Computer security controls

Refer to Security Policy.

6.6. Life cycle technical controls

Refer to SM7 "Software Development".

6.7. Network security controls

Refer to SM3.1 "Logical Security - Network".

6.8. Time-stamping

Each server synchronises with NTP. No "timestamping" service is currently offered.


CAcert defines all the meanings, semantics and profiles applicable to issuance of certificates and signatures in its policies, handbooks and other documents. Meanings that may be written in external standards or documents or found in wider conventions are not incorporated, are not used by CAcert, and must not be implied by the Member or the Non-related Person.

7.1. Certificate profile

7.1.1. Version number(s)

Issued X.509 certificates are of v3 form. The form of the PGP signatures depends on several factors, therefore no stipulation.

7.1.2. Certificate extensions

Client certificates include the following extensions:

Server certificates include the following extensions:

Code-Signing certificates include the following extensions:

OpenPGP key signatures currently do not include extensions. In the future, a serial number might be included as an extension.

7.1.3. Algorithm object identifiers

No stipulation.

7.1.4. Name forms

Refer to §3.1.1.

7.1.5. Name constraints

Refer to §3.1.1.

7.1.6. Certificate policy object identifier

The following OIDs are defined and should be incorporated into certificates:

OID Type/Meaning Comment Certification Practice Statement (this present document)

Versions are defined by additional numbers appended such as .1.

7.1.7. Usage of Policy Constraints extension

No stipulation.

7.1.8. Policy qualifiers syntax and semantics

No stipulation.

7.1.9. Processing semantics for the critical Certificate Policies extension

No stipulation.

7.2. CRL profile

7.2.1. Version number(s)

CRLs are created in X.509 v2 format.

7.2.2. CRL and CRL entry extensions

No extensions.

7.3. OCSP profile

7.3.1. Version number(s)

The OCSP responder operates in Version 1.

7.3.2. OCSP extensions

No stipulation.


There are two major threads of assessment:

See the Audit page at for more information.

8.1. Frequency or circumstances of assessment

The first audits started in late 2005, and since then, assessments have been an ongoing task. Even when completed, they are expected to be permanent features.

8.2. Identity/qualifications of assessor

Systems Auditors. CAcert uses business systems auditors with broad experience across the full range of business, information systems and security fields. In selecting a business systems auditor, CAcert looks for experience that includes but is not limited to cryptography, PKI, governance, auditing, compliance and regulatory environments, business strategy, software engineering, networks, law (including multijurisdictional issues), identity systems, fraud, IT management.

Code Auditors. See Security Policy, sections 7, 9.1.

8.3. Assessor's relationship to assessed entity

Specific internal restrictions on audit personnel:

Specific external restrictions on audit personnel:

An Auditor may convene an audit team. The same restrictions apply in general to all members of the team, but may be varied. Any deviations must be documented and approved by the CAcert Inc. Board.

8.4. Topics covered by assessment

Systems Audits are generally conducted to criteria. CAcert requires that the criteria are open:

See DRC for the current criteria. If Auditor determines that a criteria fails to follow the meet the above requirements, then the criteria should be reworked to conform, or should be dropped (both with explanatory notes).

8.5. Actions taken as a result of deficiency

See the current Audit Done list for work completed, and Audit Todo list for work in progress.

Auditor may issue directives instructing changes, where essential to audit success or other extreme situations. Directives should be grounded on criteria, on established minimum or safe practices, or clearly described logic. Adequate discussion with Community (e.g., CAcert Inc. Board and with Policy Group) should precede any directive. They should be presented to the same standard as the criteria, above.

The documents issued directives and actions.

8.6. Communication of results

Current and past Audit information is available at CAcert runs an open disclosure policy and Audit is no exception.

This CPS and other documents are subject to the process in Policy on Policy (COD1). Audits cover the overall processes more than any one document, and documents may vary even as Audit reports are delivered.


9.1. Fees

The current fees structure is posted at Changes to the fees structure will be announced from time to time on the blog. CAcert retains the right to charge fees for services. All fees are non-refundable.

9.2. Financial responsibility

Financial risks are dealt with primarily by the Dispute Resolution Policy (COD7).

9.2.1. Insurance coverage

No stipulation.

9.2.2. Other assets

No stipulation.

9.2.3. Insurance or warranty coverage for end-entities

No stipulation.

9.3. Confidentiality of business information

9.3.1. Scope of confidential information

CAcert has a policy of transparency and openness. The default posture is that information is public to the extent possible, unless covered by specific policy provisions (for example, passwords) or rulings by Arbitrator.

9.4. Privacy of personal information

Privacy is covered by the CCA (COD9) and the Privacy Policy (COD5).

9.4.1. Privacy plan

No stipulation.

9.4.2. Information treated as private

Member's Date of Birth and "Lost Password" questions are treated as fully private.

9.4.3. Information not deemed private

To the extent that information is put into an issued certificate, that information is not deemed private, as it is expected to be published by the Member as part of routine use of the certificate. Such information generally includes Names, domains, email addresses, and certificate serial numbers.

Under Assurance Policy (COD13) the Member's status (as Assured, Assurer, etc) is available to other Members.

Information placed in forums outside the online system (wiki, blogs, policies, etc) is not deemed private, and is generally deemed to be published as contributions by Members. See CCA1.3 (COD9).

9.4.4. Responsibility to protect private information

CAcert is a privacy organisation and takes privacy more seriously. Any privacy issue may be referred to dispute resolution.

9.4.5. Notice and consent to use private information

Members are permitted to rely on certificates of other Members. As a direct consequence of the general right to rely, Members may read and store the certificates and/or the information within them, where duly presented in a relationship, and to the extent necessary for the agreed relationship.

9.4.6. Disclosure pursuant to judicial or administrative process

Any disclosure pursuant to process from foreign courts (or similar) is controlled by the Arbitrator.

9.4.7. Other information disclosure circumstances


9.5. Intellectual property rights

CAcert is committed to the philosophy of an open and free Internet, broadly as encapsulated by open and free source. However, due to the strict control provisions imposed by the audit criteria (CCS), and the general environment and role of CAs, and the commitment to security of Members, some deviations are necessary.

9.5.1. Ownership and Licence

Assets that fall under the control of CCS must be transferred to CAcert. See PoP 6.2 (COD1), CCA 1.3 (COD9). That is, CAcert is free to use, modify, distribute, and otherwise conduct the business of the CA as CAcert sees fit with the asset.

9.5.2. Brand

The brand of CAcert is made up of its logo, name, trademark, service marks, etc. Use of the brand is strictly limited by the Board, and permission is required. See m20070917.5.

9.5.3. Documents

CAcert owns or requires full control over its documents, especially those covered by CCS. See PoP 6.2 (COD1). Contributors transfer the rights, see CCA 1.3 (COD9). Contributors warrant that they have the right to transfer.

Documents are generally licensed under free and open licence. See Except where explicitly negotiated, CAcert extends back to contributors a non-exclusive, unrestricted perpetual licence, permitting them to to re-use their original work freely. See PoP 6.4 (COD1), CCA 1.3 (COD9).

9.5.4. Code

CAcert owns its code or requires full control over code in use by means of a free and open licence. See CCS.

CAcert licenses its code under GPL. CAcert extends back to contributors a non-exclusive, unrestricted perpetual licence, permitting them to to re-use their original work freely.

9.5.5. Certificates and Roots

CAcert asserts its intellectual property rights over certificates issued to Members and over roots. See CCA 4.4 (COD9), CCS. The certificates may only be used by Members under COD9, and, by others under the licences offered, such as Non-Related Persons - Disclaimer and Licence (COD4).

9.6. Representations and warranties

Members. All Members of the Community agree to the CAcert Community Agreement (COD9), which is the primary document for representations and warranties. Members include Subscribers, Relying Parties, Registration Agents and the CA itself.

RAs. Registration Agents are obliged additionally by Assurance Policy, especially 3.1, 4.1 (COD13).

CA. The CA is obliged additionally by the CCS.

Third Party Vendors. Distributors of the roots are offered the 3rd-Party Vendors - Disclaimer and Licence (3PV-DaL => CODx) and are offered the same deal as Members to the extent that they agree to be Members in the Community.

9.7. Disclaimers of Warranties

Persons who have not accepted the above Agreements are offered the Non-Related Persons - Disclaimer and Licence (COD4). Any representations and warranties are strictly limited to nominal usage. In essence, NRPs may USE but must not RELY.

In today's aggressive fraud environment, and within the context of CAcert as a community CA, all parties should understand that CAcert and its Subscribers, Assurers and other roles provide service on a Best Efforts basis. See §1.4. CAcert seeks to provide an adequate minimum level of quality in operations for its Members without undue risks to NRPs. See Principles.

CAcert on behalf of the Community and itself makes no Warranty nor Guarantee nor promise that the service or certificates are adequate for the needs and circumstances.

9.8. Limitations of liability

9.9. Non-Related Persons

CAcert on behalf of related parties (RAs, Subscribers, etc) and itself disclaims all liability to NRPs in their usage of CA's certificates. See COD4.

9.10. Liabilities Between Members

Liabilities between Members are dealt with by internal dispute resolution, which rules on liability and any limits. See §9.13.

9.11. Indemnities

No stipulation.

9.12. Term and termination

9.12.1. Term

No stipulation.

9.12.2. Termination

Members file a dispute to terminate their agreement. See §9.13 and CCA 3.3 (COD9).

Documents are varied (including terminated) under COD1.

For termination of the CA, see §5.8.1.

9.12.3. Effect of termination and survival

No stipulation.

9.13. Individual notices and communications with participants

All participants are obliged to keep their listed primary email addresses in good working order. See CCA 3.5 (COD9).

9.14. Amendments

Amendments to the CPS are controlled by COD1. Any changes in Member's Agreements are notified under CCA 3.4 (COD9).

9.15. Dispute resolution provisions

CAcert provides a forum and facility for any Member or other related party to file a dispute.

Members agree to file all disputes through CAcert's forum for dispute resolution. The rules include specific provisions to assist non-Members, etc, to file dispute in this forum.

9.16. Governing law

The governing law is that of New South Wales, Australia. Disputes are generally heard before the Arbitrator under this law. Exceptionally, the Arbitrator may elect to apply the law of the parties and events, where in common, but this is unlikely because it may create results that are at odds with the Community.

9.17. Compliance with Applicable Law

9.18. Digital Signature Law

The Commonwealth and States of Australia have passed various Electronic Transactions Acts that speak to digital signatures. In summary, these acts follow the "technology neutral" model and permit but do not regulate the use of digital signatures.

This especially means that the signatures created by certificates issued by CAcert are not in and of themselves legally binding human signatures, at least according to the laws of Australia. See §1.4.3. However, certificates may play a part in larger signing applications. See §1.4.1 for "digital signing" certificates. These applications may impose significant obligations, risks and liabilities on the parties.

9.19. Privacy Law

See the Privacy Policy (COD5).

9.20. Legal Process from External Forums

CAcert will provide information about its Members only under legal subpoena or equivalent process from a court of competent jurisdiction. Any requests made by legal subpoena are treated as under the Dispute Resolution Policy See §9.13 and COD7. That is, all requests are treated as disputes, as only a duly empanelled Arbitrator has the authorisation and authority to rule on the such requests.

A subpoena should include sufficient legal basis to support an Arbitrator in ruling that information be released pursuant to the filing, including the names of claimants in any civil case and an indication as to whether the claimants are Members or not (and are therefore subject to Dispute Resolution Policy).

9.21. Miscellaneous provisions

9.21.1. Entire agreement

All Members of the Community agree to the CAcert Community Agreement (COD9). This agreement also incorporates other key documents, being this CPS, DRP and PP. See CCA 4.2.

The Configuration-Control Specification is the set of policies that rule over the Community, of which the above documents are part. See COD2. Documents that have reached full POLICY status are located at Although detailed practices may be found in other places on the website and on the wiki, the CCS documents that have reached DRAFT and POLICY status are the ruling documents.

9.21.2. Assignment

The rights within CCA may not be ordinarily assigned.

9.21.3. Severability

No stipulation.

9.21.4. Enforcement (attorneys' fees and waiver of rights)

The Arbitrator will specify fees and remedies, if any.

9.21.5. Force Majeure

No stipulation.

---This is the end of the Policy---