What is CVE-2026-6957?

CVE-2026-6957 is a high-severity vulnerability in Mattermost Legal_hold, classified under Path Traversal. CVSS score: 8.0/10. Published 2026-05-27.

How severe is CVE-2026-6957?

High severity. CVSS v3 base score is 8.0 out of 10.

Path Traversal in Mattermost Legal_hold

CVE-2026-6957

Mattermost Plugins versions <=1.1.5 fail to sanitize filenames received from federated peers before using them to construct export destination paths, which allows an administrator of a remote federated Mattermost server to write files to a…

Vulnerability class: Path Traversal (Directory Traversal)

EPSS: 0.001 (16.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.0 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H.

Affected products

Mattermost Legal_hold
Mattermost — versions 0, .0

Weakness classification (CWE)

CWE-22 — Path Traversal

References

responsibledisclosure@mattermost.com (vendor-advisory, Vendor Advisory)

Frequently asked questions

What is CVE-2026-6957?: CVE-2026-6957 is a high-severity vulnerability in Mattermost Legal_hold, classified under Path Traversal. CVSS score: 8.0/10. Published 2026-05-27.
How severe is CVE-2026-6957?: High severity. CVSS v3 base score is 8.0 out of 10.