Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%

CVE-2026-105938— Apache Pulsar: Subscription authorization policies not enforced by namespace-level backlog and unsubscribe operations and by topic expire-all

Quick assessment

Affected
Apache Software Foundation Apache Pulsar
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Apache Pulsar 的命名空间(namespace)可以限制哪些角色能够使用订阅(subscription),具体方式包括:采用“前缀订阅认证模式”(Prefix subscription authentication mode),要求订阅名称必须以角色名称开头;或者向特定角色授予对某个订阅的访问权限。主题级别的订阅操作(例如消费消息、跳过消息、重置游标或删除订阅)均会应用这些订阅策略。然而,若干作用于订阅的管理 REST API 操作并未应用这些策略,具体包括: 命名空间级别和分片(bundle)级别的清

CVSS 2.3 · Low

Affected Version Matrix 2

VendorProduct Version RangeStatus
Apache Software Foundation Apache Pulsar 2.8.0< 4.0.14 affected
4.1.0< 4.2.5 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-105938

Vulnerability Information

Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Apache Pulsar: Subscription authorization policies not enforced by namespace-level backlog and unsubscribe operations and by topic expire-all
Source: CVE Program / CVE List V5
Vulnerability Description
Apache Pulsar namespaces can restrict which roles may use a subscription, either with the Prefix subscription authentication mode, which requires a subscription name to start with the role name, or by granting permission on a subscription to specific roles. Topic-level subscription operations, such as consuming, skipping messages, resetting a cursor or deleting a subscription, apply these subscription policies. Several admin REST API operations that act on subscriptions did not apply them: - the namespace-level and bundle-level clear backlog operations, both for a named subscription and for all subscriptions; - the namespace-level and bundle-level unsubscribe operations; - the topic-level operation that expires messages for all subscriptions of a topic. With the default authorization provider, the namespace-level operations require only consume permission granted on the namespace, and the expire-all operation requires only consume permission on the topic. As a result, when authentication and authorization are enabled and a namespace uses the Prefix subscription authentication mode or subscription permissions, an authenticated user with such consume permission can clear the backlog of, expire messages of, or delete a subscription that the policies would deny to that user. Tenant admin or superuser access is not required. The clear backlog operations can also be applied to the cursors used for geo-replication, so that messages not yet replicated to a remote cluster are skipped. Deployments that do not configure the Prefix subscription authentication mode or subscription permissions (the defaults) are not affected by this bypass, because consume permission on the namespace or topic already allows these operations there. This impact analysis assumes that Pulsar has been configured with the default authorization provider. For custom authorization providers, the impact could be different. The impact is on the integrity of subscription state. Clearing or expiring the backlog moves the subscription's cursor forward, so unacknowledged messages are no longer delivered to the subscription's consumers. The unsubscribe operation deletes a subscription that has no connected consumers. Skipped messages can be permanently deleted once no other subscription or the namespace's retention policy keeps them. The issue does not allow reading message contents, changing permissions or policies, or accessing other namespaces, and it does not affect the availability of the broker. In fixed versions, the namespace-level and bundle-level operations for a named subscription apply the subscription policies to that subscription, and the operations for all subscriptions, when requested by a user who is not a tenant admin or superuser, only act on the subscriptions that the user may access. Clearing the backlog of geo-replication cursors requires tenant admin or superuser access. Topic-level subscription operations apply the subscription policies for all types of authentication data, including that of the anonymous user role. This issue affects Apache Pulsar versions from 2.8.0 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. All brokers in a cluster must be upgraded before relying on the namespace-level restrictions, because brokers that have not been upgraded do not apply them when they receive the internal per-bundle requests. 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 reduce exposure by restricting network access to the broker's admin REST API to trusted administrative clients.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
Source: CVE Program / CVE List V5
Vulnerability Type
授权机制不正确
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
Apache Software Foundation Apache Pulsar 2.8.0 ~ 4.0.14 -

II. Public POCs for CVE-2026-105938

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-105938

请登录查看更多情报信息。

Other References for CVE-2026-105938 (2)

Same Patch Batch · Apache Software Foundation · 2026-10-21 · 69 CVEs total

CVE-2026-105944 10.0 CRITICAL Apache Pulsar Manager: Missing authentication and authorization and disclosure of the Puls
CVE-2026-111812 10.0 CRITICAL Apache Traffic Server: origin_server_auth signs client-controlled AWS headers under the pr
CVE-2026-111813 10.0 CRITICAL Apache Traffic Server: magick plugin passes client query strings unfiltered to ImageMagick
CVE-2026-111815 10.0 CRITICAL Apache Traffic Server: TLS session ticket resumption bypasses per-SNI verify_client STRICT
CVE-2026-111814 10.0 CRITICAL Apache Traffic Server: Default server_session_sharing.match omits MASK_CERT, allowing pool
CVE-2026-111809 9.3 CRITICAL Apache Traffic Server: HEAD requests carrying Content-Length or Transfer-Encoding enable r
CVE-2026-111816 9.3 CRITICAL Apache Traffic Server: A malformed 302 response bypasses parse-error rejection through the
CVE-2026-105869 9.2 CRITICAL Apache Pulsar: MultiRolesTokenAuthorizationProvider uses roles from unverified tokens for
CVE-2026-111811 9.0 CRITICAL Apache Traffic Server: tsmemcache plugin exposes the shared proxy cache over the network w
CVE-2025-31699 8.9 HIGH Apache Traffic Server: Origin connection still owed a request body is reused, enabling req
CVE-2026-105937 8.7 HIGH Apache Pulsar: Missing authorization of the shadow topic source allows cross-tenant messag
CVE-2025-55702 8.7 HIGH Apache Traffic Server: An unread Expect: 100-continue request body is framed as a new requ
CVE-2026-111805 8.6 HIGH Apache Traffic Server: HTTP/2 Content-Length truncation lets a client trigger backend work
CVE-2026-111808 8.6 HIGH Apache Traffic Server: HTTP/2 DATA frame padding underflow lets a client trigger backend w
CVE-2026-111804 8.2 HIGH Apache Traffic Server: wasm plugin has a use-after-free and forwards unvalidated guest met
CVE-2026-105945 7.7 HIGH Apache Pulsar: Improper Validation of Package Name Components Allows Cross-Tenant Package
CVE-2026-105942 7.7 HIGH Apache Pulsar: Original principal of proxied requests authorized with the proxy's authenti
CVE-2026-111810 7.5 HIGH Apache Traffic Server: Unthrottled per-header diagnostic logging enables a log-flood denia
CVE-2026-105934 7.2 HIGH Apache Pulsar: Missing tenant admin authorization check when truncating a partitioned topi
CVE-2026-105930 6.0 MEDIUM Apache Pulsar: Improper Authorization of Function, Source and Sink Package URLs Allows Cro

Showing top 20 of 69 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

V. Comments for CVE-2026-105938

No comments yet


Leave a comment