CVE-2026-6961CWE-22

CVE-2026-6961: Path traversal via unsanitized FileInfo.Name in Mattermost federation sync

High · published June 12, 2026

CVSS v3.1
7.6
EPSS
0%
Percentile
38.3
In the wild
Unconfirmed
What it is

Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 Mattermost fails to sanitize FileInfo.Name received from federated peers during shared channel file sync, which allows an attacker who controls a federated server to write files to arbitrary locations within the target server's filestore via path traversal sequences in the filename field.. Mattermost Advisory ID: MMSA-2026-00661

The record
Technical detail
CVSS v3.1
7.6 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:L
CVSS v4.0
Not supplied
EPSS
0.00452 · 38.3th percentile
Weakness
CWE-22 · Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Published
2026-06-12T15:56Z
EPSS history
Timeline
  • 12 JUN 15:56Z
    CVE-2026-6961: Path traversal via unsanitized FileInfo.Name in Mattermost federation sync
    cvelistv5