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Full vulnerability report · 2026
CVE-2026-105869High confidence

Apache Pulsar: MultiRolesTokenAuthorizationProvider uses roles from unverified tokens for HTTP requests that fall back to the anonymous user role

Apache Software Foundation · Apache Pulsar

9.2CriticalCVSS 4.0
Recommended action
Within 72 hours

Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded.

Fix not verified
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityCriticalOperational priority:Critical, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 0.30% for the current model date.

Compensating controls

  • Restrict the affected network interface to trusted sources where business-safe.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Apache Software Foundation Apache Pulsar and falls inside the recorded affected range.
  2. Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: Within 3 daysRemediation target: Within 90 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2026-107422

No EUVD known-exploited evidence

Apache Pulsar's MultiRolesTokenAuthorizationProvider authorizes a client with all roles listed in a claim of its JSON Web Token (JWT). The provider is intended for use with token authentication, which verifies the token before authorization. The provider did not verify the token itself: it parsed the token's claims with the signature removed and trusted that authentication had already checked it. When authentication and authorization are enabled with a non-empty anonymousUserRole setting, some HTTP requests whose credentials fail authentication are not rejected, but are handled as requests of the anonymous user role. For the broker's HTTP endpoints, such as the admin REST API, this fallback applies to requests that do not name an authentication method and requires strictAuthMethod to be false (the default) where that setting is available. For the WebSocket API, failed credentials can also fall back to the anonymous user role; this path does not enforce strictAuthMethod. The authentication data kept for such a request still contained the request's Authorization header. MultiRolesTokenAuthorizationProvider then read the bearer token from that header without verifying its signature and authorized the request with the roles in the token's role claim. As a result, in deployments that use MultiRolesTokenAuthorizationProvider together with a non-empty anonymousUserRole and that permit this fallback, an unauthenticated client can send an HTTP request, for example to the admin REST API or the WebSocket API, with a forged or unsigned token that lists arbitrary roles, and be authorized with those roles. The impact can include super-user access when the token lists a role configured in superUserRoles, allowing the client to read and change tenants, namespaces, topics, permissions and broker configuration. No valid credentials are required. Deployments are not affected if they use the default authorization provider (PulsarAuthorizationProvider) or another authorization provider, or if anonymousUserRole is not set (the default). Requests that authenticate successfully with a valid token are not affected, because the token that MultiRolesTokenAuthorizationProvider reads is the token that authentication verified. Connections that use the Pulsar binary protocol are not affected by this issue, because the broker does not keep client authentication data for connections that it assigns to the anonymous user role. In fixed versions, MultiRolesTokenAuthorizationProvider obtains roles only from tokens that the configured token authentication provider has verified, using its configured keys and validation settings. Broker HTTP requests that are assigned to the anonymous user role are authorized only as that role, and invalid tokens cannot supply additional roles to WebSocket requests. The broker fails to start if MultiRolesTokenAuthorizationProvider is configured with authorization enabled but without a token authentication provider. This issue affects Apache Pulsar versions from 2.8.1 before 4.0.14 and from 4.1.0 before 4.2.5. - 4.0.x version users should upgrade to at least 4.0.14. - 4.1.x and 4.2.x version users should upgrade to at least 4.2.5. Users operating versions prior to those listed above should upgrade to the aforementioned patched versions or newer versions. The currently supported Apache Pulsar release lines are 4.0.x and 5.0.x. The supported versions schedule is available at https://pulsar.apache.org/contribute/release-policy/. Users who cannot upgrade immediately can remove the anonymousUserRole setting from the broker and WebSocket service configurations, or restrict network access to the HTTP endpoints of these services to trusted clients.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
9.2 · CVSS 4.0
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 72 hours

Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded.

Fix not verified
01

What, why and how

Apache Pulsar's MultiRolesTokenAuthorizationProvider authorizes a client with all roles listed in a claim of its JSON Web Token (JWT). The provider is intended for use with token authentication, which verifies the token before authorization. The provider did not verify the token itself: it parsed the token's claims with the signature removed and trusted that authentication had already checked it. When authentication and authorization are enabled with a non-empty anonymousUserRole setting, some HTTP requests whose credentials fail authentication are not rejected, but are handled as requests of the anonymous user role. For the broker's HTTP endpoints, such as the admin REST API, this fallback applies to requests that do not name an authentication method and requires strictAuthMethod to be false (the default) where that setting is available. For the WebSocket API, failed credentials can also fall back to the anonymous user role; this path does not enforce strictAuthMethod. The authentication data kept for such a request still contained the request's Authorization header. MultiRolesTokenAuthorizationProvider then read the bearer token from that header without verifying its signature and authorized the request with the roles in the token's role claim. As a result, in deployments that use MultiRolesTokenAuthorizationProvider together with a non-empty anonymousUserRole and that permit this fallback, an unauthenticated client can send an HTTP request, for example to the admin REST API or the WebSocket API, with a forged or unsigned token that lists arbitrary roles, and be authorized with those roles. The impact can include super-user access when the token lists a role configured in superUserRoles, allowing the client to read and change tenants, namespaces, topics, permissions and broker configuration. No valid credentials are required. Deployments are not affected if they use the default authorization provider (PulsarAuthorizationProvider) or another authorization provider, or if anonymousUserRole is not set (the default). Requests that authenticate successfully with a valid token are not affected, because the token that MultiRolesTokenAuthorizationProvider reads is the token that authentication verified. Connections that use the Pulsar binary protocol are not affected by this issue, because the broker does not keep client authentication data for connections that it assigns to the anonymous user role. In fixed versions, MultiRolesTokenAuthorizationProvider obtains roles only from tokens that the configured token authentication provider has verified, using its configured keys and validation settings. Broker HTTP requests that are assigned to the anonymous user role are authorized only as that role, and invalid tokens cannot supply additional roles to WebSocket requests. The broker fails to start if MultiRolesTokenAuthorizationProvider is configured with authorization enabled but without a token authentication provider. This issue affects Apache Pulsar versions from 2.8.1 before 4.0.14 and from 4.1.0 before 4.2.5. - 4.0.x version users should upgrade to at least 4.0.14. - 4.1.x and 4.2.x version users should upgrade to at least 4.2.5. Users operating versions prior to those listed above should upgrade to the aforementioned patched versions or newer versions. The currently supported Apache Pulsar release lines are 4.0.x and 5.0.x. The supported versions schedule is available at https://pulsar.apache.org/contribute/release-policy/. Users who cannot upgrade immediately can remove the anonymousUserRole setting from the broker and WebSocket service configurations, or restrict network access to the HTTP endpoints of these services to trusted clients.

What

Apache Pulsar's MultiRolesTokenAuthorizationProvider authorizes a client with all roles listed in a claim of its JSON Web Token (JWT). The provider is intended for use with token authentication, which verifies the token before authorization. The provider did not verify the token itself: it parsed the token's claims with the signature removed and trusted that authentication had already checked it. When authentication and authorization are enabled with a non-empty anonymousUserRole setting, some HTTP requests whose credentials fail authentication are not rejected, but are handled as requests of the anonymous user role. For the broker's HTTP endpoints, such as the admin REST API, this fallback applies to requests that do not name an authentication method and requires strictAuthMethod to be false (the default) where that setting is available. For the WebSocket API, failed credentials can also fall back to the anonymous user role; this path does not enforce strictAuthMethod. The authentication data kept for such a request still contained the request's Authorization header. MultiRolesTokenAuthorizationProvider then read the bearer token from that header without verifying its signature and authorized the request with the roles in the token's role claim. As a result, in deployments that use MultiRolesTokenAuthorizationProvider together with a non-empty anonymousUserRole and that permit this fallback, an unauthenticated client can send an HTTP request, for example to the admin REST API or the WebSocket API, with a forged or unsigned token that lists arbitrary roles, and be authorized with those roles. The impact can include super-user access when the token lists a role configured in superUserRoles, allowing the client to read and change tenants, namespaces, topics, permissions and broker configuration. No valid credentials are required. Deployments are not affected if they use the default authorization provider (PulsarAuthorizationProvider) or another authorization provider, or if anonymousUserRole is not set (the default). Requests that authenticate successfully with a valid token are not affected, because the token that MultiRolesTokenAuthorizationProvider reads is the token that authentication verified. Connections that use the Pulsar binary protocol are not affected by this issue, because the broker does not keep client authentication data for connections that it assigns to the anonymous user role. In fixed versions, MultiRolesTokenAuthorizationProvider obtains roles only from tokens that the configured token authentication provider has verified, using its configured keys and validation settings. Broker HTTP requests that are assigned to the anonymous user role are authorized only as that role, and invalid tokens cannot supply additional roles to WebSocket requests. The broker fails to start if MultiRolesTokenAuthorizationProvider is configured with authorization enabled but without a token authentication provider. This issue affects Apache Pulsar versions from 2.8.1 before 4.0.14 and from 4.1.0 before 4.2.5. - 4.0.x version users should upgrade to at least 4.0.14. - 4.1.x and 4.2.x version users should upgrade to at least 4.2.5. Users operating versions prior to those listed above should upgrade to the aforementioned patched versions or newer versions. The currently supported Apache Pulsar release lines are 4.0.x and 5.0.x. The supported versions schedule is available at https://pulsar.apache.org/contribute/release-policy/. Users who cannot upgrade immediately can remove the anonymousUserRole setting from the broker and WebSocket service configurations, or restrict network access to the HTTP endpoints of these services to trusted clients.

Why

The product does not verify, or incorrectly verifies, the cryptographic signature for data.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

Apache Pulsar's MultiRolesTokenAuthorizationProvider authorizes a client with all roles listed in a claim of its JSON Web Token (JWT). The provider is intended for use with token authentication, which verifies the token before authorization. The provider did not verify the token itself: it parsed the token's claims with the signature removed and trusted that authentication had already checked it. When authentication and authorization are enabled with a non-empty anonymousUserRole setting, some HTTP requests whose credentials fail authentication are not rejected, but are handled as requests of the anonymous user role. For the broker's HTTP endpoints, such as the admin REST API, this fallback applies to requests that do not name an authentication method and requires strictAuthMethod to be false (the default) where that setting is available. For the WebSocket API, failed credentials can also fall back to the anonymous user role; this path does not enforce strictAuthMethod. The authentication data kept for such a request still contained the request's Authorization header. MultiRolesTokenAuthorizationProvider then read the bearer token from that header without verifying its signature and authorized the request with the roles in the token's role claim. As a result, in deployments that use MultiRolesTokenAuthorizationProvider together with a non-empty anonymousUserRole and that permit this fallback, an unauthenticated client can send an HTTP request, for example to the admin REST API or the WebSocket API, with a forged or unsigned token that lists arbitrary roles, and be authorized with those roles. The impact can include super-user access when the token lists a role configured in superUserRoles, allowing the client to read and change tenants, namespaces, topics, permissions and broker configuration. No valid credentials are required. Deployments are not affected if they use the default authorization provider (PulsarAuthorizationProvider) or another authorization provider, or if anonymousUserRole is not set (the default). Requests that authenticate successfully with a valid token are not affected, because the token that MultiRolesTokenAuthorizationProvider reads is the token that authentication verified. Connections that use the Pulsar binary protocol are not affected by this issue, because the broker does not keep client authentication data for connections that it assigns to the anonymous user role. In fixed versions, MultiRolesTokenAuthorizationProvider obtains roles only from tokens that the configured token authentication provider has verified, using its configured keys and validation settings. Broker HTTP requests that are assigned to the anonymous user role are authorized only as that role, and invalid tokens cannot supply additional roles to WebSocket requests. The broker fails to start if MultiRolesTokenAuthorizationProvider is configured with authorization enabled but without a token authentication provider. This issue affects Apache Pulsar versions from 2.8.1 before 4.0.14 and from 4.1.0 before 4.2.5. - 4.0.x version users should upgrade to at least 4.0.14. - 4.1.x and 4.2.x version users should upgrade to at least 4.2.5. Users operating versions prior to those listed above should upgrade to the aforementioned patched versions or newer versions. The currently supported Apache Pulsar release lines are 4.0.x and 5.0.x. The supported versions schedule is available at https://pulsar.apache.org/contribute/release-policy/. Users who cannot upgrade immediately can remove the anonymousUserRole setting from the broker and WebSocket service configurations, or restrict network access to the HTTP endpoints of these services to trusted clients.

Why

The product does not verify, or incorrectly verifies, the cryptographic signature for data.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Improper Verification of Cryptographic Signature → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Not a CVSS 4.0 base metric
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-347 ↗

CWE-347: Improper Verification of Cryptographic Signature. The product does not verify, or incorrectly verifies, the cryptographic signature for data.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Common Vulnerability Scoring System 4.0: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.ATPresentAttack requirements: A particular deployment or execution condition must be present.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.VCHighVulnerable-system confidentiality: A successful attack can cause a major loss.VIHighVulnerable-system integrity: A successful attack can cause a major loss.VAHighVulnerable-system availability: A successful attack can cause a major loss.SCNoneSubsequent-system confidentiality: No direct loss is represented by this metric.SINoneSubsequent-system integrity: No direct loss is represented by this metric.SANoneSubsequent-system availability: No direct loss is represented by this metric.
Post-exploitation / living off the land
Stolen credentials, tokens and legitimate administration functions may provide continued access without deploying a large custom toolset.
NetworkUnauthenticatedCWE-347
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2026-107422Official EUVD mapping

Apache Pulsar's MultiRolesTokenAuthorizationProvider authorizes a client with all roles listed in a claim of its JSON Web Token (JWT). The provider is intended for use with token authentication, which verifies the token before authorization. The provider did not verify the token itself: it parsed the token's claims with the signature removed and trusted that authentication had already checked it. When authentication and authorization are enabled with a non-empty anonymousUserRole setting, some HTTP requests whose credentials fail authentication are not rejected, but are handled as requests of the anonymous user role. For the broker's HTTP endpoints, such as the admin REST API, this fallback applies to requests that do not name an authentication method and requires strictAuthMethod to be false (the default) where that setting is available. For the WebSocket API, failed credentials can also fall back to the anonymous user role; this path does not enforce strictAuthMethod. The authentication data kept for such a request still contained the request's Authorization header. MultiRolesTokenAuthorizationProvider then read the bearer token from that header without verifying its signature and authorized the request with the roles in the token's role claim. As a result, in deployments that use MultiRolesTokenAuthorizationProvider together with a non-empty anonymousUserRole and that permit this fallback, an unauthenticated client can send an HTTP request, for example to the admin REST API or the WebSocket API, with a forged or unsigned token that lists arbitrary roles, and be authorized with those roles. The impact can include super-user access when the token lists a role configured in superUserRoles, allowing the client to read and change tenants, namespaces, topics, permissions and broker configuration. No valid credentials are required. Deployments are not affected if they use the default authorization provider (PulsarAuthorizationProvider) or another authorization provider, or if anonymousUserRole is not set (the default). Requests that authenticate successfully with a valid token are not affected, because the token that MultiRolesTokenAuthorizationProvider reads is the token that authentication verified. Connections that use the Pulsar binary protocol are not affected by this issue, because the broker does not keep client authentication data for connections that it assigns to the anonymous user role. In fixed versions, MultiRolesTokenAuthorizationProvider obtains roles only from tokens that the configured token authentication provider has verified, using its configured keys and validation settings. Broker HTTP requests that are assigned to the anonymous user role are authorized only as that role, and invalid tokens cannot supply additional roles to WebSocket requests. The broker fails to start if MultiRolesTokenAuthorizationProvider is configured with authorization enabled but without a token authentication provider. This issue affects Apache Pulsar versions from 2.8.1 before 4.0.14 and from 4.1.0 before 4.2.5. - 4.0.x version users should upgrade to at least 4.0.14. - 4.1.x and 4.2.x version users should upgrade to at least 4.2.5. Users operating versions prior to those listed above should upgrade to the aforementioned patched versions or newer versions. The currently supported Apache Pulsar release lines are 4.0.x and 5.0.x. The supported versions schedule is available at https://pulsar.apache.org/contribute/release-policy/. Users who cannot upgrade immediately can remove the anonymousUserRole setting from the broker and WebSocket service configurations, or restrict network access to the HTTP endpoints of these services to trusted clients.

Official EUVD record ↗
INCIBE-CERT · Spanish · multiples-vulnerabilidades-en-productos-de-apacheMúltiples vulnerabilidades en productos de Apache

George Chen y otros investigadores, junto con la comunidad de Apache, han informado sobre 16 vulnerabilidades en Apache Pulsar y Apache Traffic Server: 5 de severidad crítica, 9 alta y 2 media. Su explotación podría permitir obtener privilegios de superusuario, eludir controles de acceso, manipular peticiones o respuestas HTTP, acceder, modificar o eliminar información de la caché y provocar una denegación de servicio.

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Fix not verified
Affected
Apache Pulsar: 2.8.1 < 4.0.14, 4.1.0 < 4.2.5
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 21 Oct 2026 · Last source change 21 Oct 2026, 17:58 UTC · CWE-347 · Improper Verification of Cryptographic Signature

CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-10-22
European sourceENISA EUVD · EUVD-2026-107422
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD awaiting enrichment

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗
  1. ENISA EUVD mappingEUVD-2026-107422 was added to the official ENISA EUVD mapping for this CVE.
    Before
    not recorded
    After
    {"euvdId":"EUVD-2026-107422"}
    ENISA EUVD ↗
  2. Vendor guidanceAuthoritative vendor guidance changed: removed vendor advisory: lists.apache.org/lf36z1tlcsokp4gv97obkdjtt74ngmrw; removed vendor advisory: pulsar.apache.org/CVE-2026-105869.
    Before
    vendor advisory: lists.apache.org/lf36z1tlcsokp4gv97obkdjtt74ngmrw · vendor advisory: pulsar.apache.org/CVE-2026-105869
    After
    no authoritative guidance recorded
    CNA ↗
  3. Catalogue recordCVE added to the BlackTree catalogue.
    CNA ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
ENISA EUVD · EUVD-2026-107422↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2026-105869 · cve.blacktree.nl