CVE-2026-2457 — WebSocket Message Spoofing via Permalink Embed Manipulation
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to sanitize client-supplied post metadata which allows an authenticated attacker to spoof permal…
Published: 2026-03-16 · CVSS: 4.3 · CVSS 3.1
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to sanitize client-supplied post metadata which allows an authenticated attacker to spoof permalink embeds impersonating other users via crafted PUT requests to the post update API endpoint.. Mattermost Advisory ID: MMSA-2025-00569
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7