CVE-2025-11776

low-risk

Published 2025-11-14

Mattermost versions <11 fail to properly restrict access to archived channel search API which allows guest users to discover archived public channels via the `/api/v4/teams/{team_id}/channels/search_archived` endpoint

Do I need to act?

0.03% chance of exploitation

EPSS score — low exploit probability

Not on CISA KEV list

No confirmed active exploitation reported to CISA

Patch status unknown

Check vendor advisories for fix availability and mitigation guidance

CVSS 4.3/10 Medium

NETWORK / LOW complexity

Affected Products (1)

Mattermost Server

Affected Vendors

Mattermost

References (1)

Vendor Advisory https://mattermost.com/security-updates

/ 100

low-risk

Severity 18/34 · Moderate

Exploitability 0/34 · Minimal

Exposure 5/34 · Minimal