CVE-2026-25742

Summary

Zulip is an open-source team collaboration tool. Prior to version 11.6, Zulip is an open-source team collaboration tool. From version 1.4.0 to before version 11.6, even after spectator access (enable_spectator_access / WEB_PUBLIC_STREAMS_ENABLED) is disabled, attachments originating from web-public streams can still be retrieved anonymously. As a result, file contents remain accessible even after public access is intended to be disabled. Similarly, even after spectator access is disabled, the /users/me/<stream_id>/topics endpoint remains reachable anonymously, allowing retrieval of topic history for web-public streams. This issue has been patched in version 11.6. This issue has been patched in version 11.6.

Impact & exploitability

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Affected products we track (1)

Recommendation

Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.

Official patch: https://github.com/zulip/zulip/commit/3c045414299680b9f5dca7d76cf6cef6121c0236 ↗

Additional information

• NVD record
• https://github.com/zulip/zulip/commit/3c045414299680b9f5dca7d76cf6cef6121c0236Patch
• https://github.com/zulip/zulip/commit/41e23347b5218b3b0397a55176c7d97396735baePatch
• https://github.com/zulip/zulip/security/advisories/GHSA-f47p-xjqq-g28wAdvisory
• https://github.com/zulip/zulip/releases/tag/11.6