https://cve.radiocsirt.org/rss/recent/all/10 Most recent entries from all 2026-10-09T19:30:14.217698+00:00 Vulnerability-Lookup csirt@opendfir.org python-feedgen Contains only the most 10 recent entries. https://cve.radiocsirt.org/vuln/cve-2026-28759 CVE-2026-28759 — Insufficient authorization in shared channel membership sync allows remote cluster to remove users from arbitrary chann… 2026-10-09T19:30:14.233403+00:00

Affected: Mattermost

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to validate that a remote cluster has access to a channel before processing membership removal requests during shared channel membership sync, which allows a malicious remote cluster to remove any user from any channel, including private channels, via crafted membership sync messages targeting channels the remote cluster is not authorized to access. Mattermost Advisory ID: MMSA-2026-00576