Description
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.
Affected products
zulip: zulip
References5
- github.com/zulip/zulip/security/advisories/GHSA-f47p-xjqq-g28w ExploitVendor Advisory
- github.com/zulip/zulip/security/advisories/GHSA-f47p-xjqq-g28w ExploitVendor Advisory
- github.com/zulip/zulip/commit/3c045414299680b9f5dca7d76cf6cef61… Patch
- github.com/zulip/zulip/commit/41e23347b5218b3b0397a55176c7d9739… Patch
- github.com/zulip/zulip/releases/tag/11.6 Release Notes
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - EPSS — exploit probability
- 0% percentile: 26 · as of 12 November 2026
- CWE
- CWE-862
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