GHSA-424h-xj87-m937Published

Mattermost has an Incorrect Authorization vulnerability

Exact source revision recorded 24 Oct 2026 13:19:41 UTC. It does not establish the source's current position. Latest evidence.

Recorded JSON

osv · GHSA-424h-xj87-m937

Published

Mattermost versions 10.5.x <= 10.5.10, 10.11.x <= 10.11.2 fail to properly validate guest user permissions when adding channel members which allows guest users to add any team members to their private channels via the `/api/v4/channels/{channel_id}/members` endpoint

Source published: 16 Oct 2025 09:30:24 UTC
Source modified: 5 Nov 2025 19:57:40 UTC
Observed here: 24 Oct 2026 13:19:41 UTC
Source terms: GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N

Publisher rating · LOW