Evidence used
- No CISA KEV confirmation is currently recorded.
- EPSS is 0.41% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2026
CVE-2026-105936High confidence
Apache Pulsar: Functions connectors list endpoint does not apply the super-user check of the worker connectors endpoint
Apache Software Foundation · Apache Pulsar
5.3MediumCVSS 4.0
Scheduled
Fix not verifiedMedium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityMedium→Operational priority:Medium, unchanged from published severity.unchanged
Compensating controls
- Restrict the affected network interface to trusted sources where business-safe.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs Apache Software Foundation Apache Pulsar and falls inside the recorded affected range.
- Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.
Fix not verified01
What, why and how
The Pulsar Functions worker REST API provides two endpoints that return the catalog of Pulsar IO connectors installed on the functions worker: the worker connectors endpoint (/admin/v2/worker/connectors) and the deprecated functions connectors endpoint (/admin/v2/functions/connectors and /admin/v3/functions/connectors). When authorization is enabled, the worker connectors endpoint requires super-user access. The functions connectors endpoint, served both by the functions worker and by a broker running the functions worker, returns the same catalog without this check. As a result, when authentication and authorization are enabled, any authenticated client can read the connector catalog through the functions connectors endpoint, regardless of the permissions granted to its role and without super-user access. Unauthenticated requests are rejected unless anonymous access is configured with an anonymous user role. The catalog contains the connector type definitions installed in the functions worker's connectors directory: the connector name, its description, and the source, sink and configuration class names. It does not contain configured source or sink instances, their configuration values or credentials, and an installed connector type does not indicate that a connector is configured or running. The impact is limited to disclosure of this metadata, which can include the names and descriptions of custom connectors installed by the operator. The issue does not allow modifying the catalog or managing connectors. Connector definitions that have a source or sink class are also returned by the built-in sources and sinks endpoints to authenticated clients. In fixed versions, the functions connectors endpoint applies the same checks as the worker connectors endpoint, so that it requires super-user access when authorization is enabled. Clients that are not super-users can use the built-in sources and sinks endpoints to list the available connector types. This issue affects Apache Pulsar versions from 2.4.1 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/.
What
The Pulsar Functions worker REST API provides two endpoints that return the catalog of Pulsar IO connectors installed on the functions worker: the worker connectors endpoint (/admin/v2/worker/connectors) and the deprecated functions connectors endpoint (/admin/v2/functions/connectors and /admin/v3/functions/connectors). When authorization is enabled, the worker connectors endpoint requires super-user access. The functions connectors endpoint, served both by the functions worker and by a broker running the functions worker, returns the same catalog without this check. As a result, when authentication and authorization are enabled, any authenticated client can read the connector catalog through the functions connectors endpoint, regardless of the permissions granted to its role and without super-user access. Unauthenticated requests are rejected unless anonymous access is configured with an anonymous user role. The catalog contains the connector type definitions installed in the functions worker's connectors directory: the connector name, its description, and the source, sink and configuration class names. It does not contain configured source or sink instances, their configuration values or credentials, and an installed connector type does not indicate that a connector is configured or running. The impact is limited to disclosure of this metadata, which can include the names and descriptions of custom connectors installed by the operator. The issue does not allow modifying the catalog or managing connectors. Connector definitions that have a source or sink class are also returned by the built-in sources and sinks endpoints to authenticated clients. In fixed versions, the functions connectors endpoint applies the same checks as the worker connectors endpoint, so that it requires super-user access when authorization is enabled. Clients that are not super-users can use the built-in sources and sinks endpoints to list the available connector types. This issue affects Apache Pulsar versions from 2.4.1 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/.
Why
The application reaches a protected operation without first confirming that the requester is authorised.
How
An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
The Pulsar Functions worker REST API provides two endpoints that return the catalog of Pulsar IO connectors installed on the functions worker: the worker connectors endpoint (/admin/v2/worker/connectors) and the deprecated functions connectors endpoint (/admin/v2/functions/connectors and /admin/v3/functions/connectors). When authorization is enabled, the worker connectors endpoint requires super-user access. The functions connectors endpoint, served both by the functions worker and by a broker running the functions worker, returns the same catalog without this check. As a result, when authentication and authorization are enabled, any authenticated client can read the connector catalog through the functions connectors endpoint, regardless of the permissions granted to its role and without super-user access. Unauthenticated requests are rejected unless anonymous access is configured with an anonymous user role. The catalog contains the connector type definitions installed in the functions worker's connectors directory: the connector name, its description, and the source, sink and configuration class names. It does not contain configured source or sink instances, their configuration values or credentials, and an installed connector type does not indicate that a connector is configured or running. The impact is limited to disclosure of this metadata, which can include the names and descriptions of custom connectors installed by the operator. The issue does not allow modifying the catalog or managing connectors. Connector definitions that have a source or sink class are also returned by the built-in sources and sinks endpoints to authenticated clients. In fixed versions, the functions connectors endpoint applies the same checks as the worker connectors endpoint, so that it requires super-user access when authorization is enabled. Clients that are not super-users can use the built-in sources and sinks endpoints to list the available connector types. This issue affects Apache Pulsar versions from 2.4.1 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/.
Why
The application reaches a protected operation without first confirming that the requester is authorised.
How
An attacker operating through a network path may attempt exploitation with low privileges. 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 No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.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 None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.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 → Missing Authorization → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Network
- Privileges required
- Low: a basic authenticated account is required
- 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-862 ↗
CWE-862: Missing Authorization. The product does not perform an authorization check when an actor attempts to access a resource or perform an action.
- 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:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:NCommon 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.ATNoneAttack requirements: No additional deployment or execution condition is required.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.VCLowVulnerable-system confidentiality: A successful attack can cause a limited loss.VINoneVulnerable-system integrity: No direct loss is represented by this metric.VANoneVulnerable-system availability: No direct loss is represented by this metric.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.
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: 2.4.1 < 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, 18:11 UTC · CWE-862 · Missing Authorization
CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-10-22
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2026-107473
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
View recent updates ↗What changed after publication
- ENISA EUVD mappingEUVD-2026-107473 was added to the official ENISA EUVD mapping for this CVE.ENISA EUVD ↗
- Before
- not recorded
- After
- {"euvdId":"EUVD-2026-107473"}
- Vendor guidanceAuthoritative vendor guidance changed: removed vendor advisory: lists.apache.org/dn0cg4l3yolw90f8rjyvv4dl7k340jkz; removed vendor advisory: pulsar.apache.org/CVE-2026-105936.CNA ↗
- Before
- vendor advisory: lists.apache.org/dn0cg4l3yolw90f8rjyvv4dl7k340jkz · vendor advisory: pulsar.apache.org/CVE-2026-105936
- After
- no authoritative guidance recorded
- Catalogue recordCVE added to the BlackTree catalogue.CNA ↗
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.