Vulnerability · Published Aug 17, 2026 · Assigned by Mattermost

CVE-2026-16045Delegated OAuth tokens could revoke unrelated OAuth application authorizations

Low 2.7

In plain English

A low-severity incorrect authorization in Mattermost from Mattermost. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 26% of all known vulnerabilities).

Severity (CVSS 3.1)2.7Low

Exploit odds (30 days)0.3%top 73.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 Mattermost failed to restrict OAuth deauthorization and personal access token management endpoints to direct user sessions, which allowed an OAuth app with a delegated user token to revoke the user's authorizations or tokens for other integrations via account-management endpoints.. Mattermost Advisory ID: MMSA-2026-00704

Affected products (as reported)

Vendor	Product	Versions
Mattermost	Mattermost	11.7.0 – through 11.7.610.11.0 – through 10.11.21

Weakness: CWE-863 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

References

MMSA-2026-00704 vendor-advisory