GO-2026-5263
Mattermost doesn't verify channel membership when processing AI-assisted message rewrites in github.com/mattermost/mattermost-server
Details
Mattermost doesn't verify channel membership when processing AI-assisted message rewrites in github.com/mattermost/mattermost-server.
NOTE: The source advisory for this report contains additional versions that could not be automatically mapped to standard Go module versions.
(If this is causing false-positive reports from vulnerability scanners, please suggest an edit to the report.)
The additional affected modules and versions are: github.com/mattermost/mattermost-server/v5 before v5.3.2-0.20260401090745-f4d1abe7e8f5.
Are you affected?
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Affected packages
11.5.0+incompatible Fixed in: 11.5.2+incompatible go get github.com/mattermost/mattermost-server@v11.5.2+incompatible 0 No fixed version published yet for github.com/mattermost/mattermost-server/v5 (go modules). Pin to a known-safe version or switch to an alternative.
0 No fixed version published yet for github.com/mattermost/mattermost-server/v6 (go modules). Pin to a known-safe version or switch to an alternative.
0 Fixed in: 8.0.0-20260401090745-f4d1abe7e8f5 go get github.com/mattermost/mattermost/server/v8@v8.0.0-20260401090745-f4d1abe7e8f5