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| Package Name | Ecosystem | Vulnerable Versions | First Patched Version |
|---|---|---|---|
| github.com/mattermost/mattermost/server/v8 | go | >= 8.0.0-20260304132957-9f2616376582, < 8.0.0-20260320113102-f2b3d1c6a945 | 8.0.0-20260320113102-f2b3d1c6a945 |
Miggo AIRoot Cause AnalysisThe analysis of the provided patch (commit f2b3d1c6a945) reveals an incorrect authorization vulnerability in Mattermost's post editing functionality. The functions api4.updatePost and api4.postPatchChecks in server/channels/api4/post.go did not properly verify user permissions before allowing a post to be modified.
Specifically, the system failed to check if a user attempting to edit a post still retained create_post permissions within the corresponding channel. This oversight allowed users who had their creation permissions revoked to still be able to modify existing content, thereby bypassing channel moderation policies. The vulnerability was present in the API handlers for both PUT and PATCH requests for posts.
The patch addresses this by introducing a userCreatePostPermissionCheckWithContext call at the beginning of both functions. This ensures that the user's permission to create posts is validated before any edit or patch operation is allowed to proceed.
It is important to note that the vulnerability description provided refers to an issue with "playbook run creation," which contradicts the evidence found in the associated patch. The analysis is based solely on the provided commit, which clearly points to a flaw in post editing, not playbook creation.
