CVEvulnerability
CVE-2026-4915
6.5 MEDIUM
Official page ↗
- Status
- Analyzed
- Published
- 2026-05-25
- Last modified
- 2026-07-23
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 6.5 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Weaknesses
- CWE-754
Description
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to filter nil elements from outgoing webhook attachment payloads before processing, which allows an authenticated user to cause a denial of service (server process termination) via a crafted webhook callback response containing a null attachment entry.. Mattermost Advisory ID: MMSA-2026-00641
Affected configurations
• mattermost mattermost server (>= 10.11.0 < 10.11.15)
• mattermost mattermost server (>= 11.4.0 < 11.4.5)
• mattermost mattermost server (>= 11.5.0 < 11.5.4)
• mattermost mattermost server (>= 11.6.0 < 11.6.1)
Related
Weakness · CWE (1)
- CWE-754 Improper Check for Unusual or Exceptional Conditions weakness
References
- https://mattermost.com/security-updates Vendor Advisory