CVE-2026-4646 — Insufficient input validation in GitHub plugin API causes denial of service
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to validate user-supplied input in API request handlers which allows an authen…
Published: 2026-05-22 · CVSS: 4.3 · CVSS 3.1
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to validate user-supplied input in API request handlers which allows an authenticated attacker to crash the plugin process via a crafted HTTP request to the PR details endpoint.. Mattermost Advisory ID: MMSA-2026-00638
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7