CVE-2026-2457CWE-346

WebSocket Message Spoofing via Permalink Embed Manipulation

Medium · published March 16, 2026

CVSS v3.1
4.3
EPSS
0%
Percentile
1.2
In the wild
Unconfirmed
What it is

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

The record
Technical detail
CVSS v3.1
4.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00109 · 1.2th percentile
Weakness
CWE-346 · Origin Validation Error
Published
2026-03-16T11:20Z
EPSS history
Timeline
  • 16 MAR 11:20Z
    WebSocket Message Spoofing via Permalink Embed Manipulation
    cvelistv5