CVE-2026-91181

CVE CVE-2026-91181EUVD EUVD-2026-78160Published 2026-09-14T21:21:47.000ZLast changed 2026-09-16T03:56:15.000ZCVSS 6.5

What the advisory describes

Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 Fail to sanitize Team objects returned by the data retention teams endpoint which allows an authenticated user holding only the read-only Data Retention Policy permission to obtain a private team's secret invite_id and email, and use it to join the team without authorization, via GET /api/v4/data_retention/policies/{policy_id}/teams.. Mattermost Advisory ID: MMSA-2026-00702

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

Mattermost — Mattermost 11.9.0 ≤11.9.0; 10.11.0 ≤10.11.22; 11.8.0 ≤11.8.4; 11.7.0 ≤11.7.7

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.

Mattermost — Mattermost

Does this concern one of your customers?

This page cannot answer that — it does not know your estate. Whoever has recorded their environments gets the answer the morning after publication, together with a paragraph they can forward to the customer unedited.

Try it for 28 days

Patchlage reports hits and suspected hits. About everything else this system says nothing — neither this page nor the situation report ever claims that an estate is safe.