CVEvulnerability
CVE-2026-86349
4.3 MEDIUM
Official page ↗
- Status
- Analyzed
- Published
- 2026-09-14
- Last modified
- 2026-10-07
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 4.3 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
- Weaknesses
- CWE-407
Description
Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.8, 10.11.x <= 10.11.22 fail to limit the nesting depth in the server-side Markdown parser which allows an authenticated attacker to cause a denial of service (CPU resource exhaustion) via a crafted post containing deeply nested blockquotes or list items.. Mattermost Advisory ID: MMSA-2026-00707
Affected configurations
• mattermost mattermost server (>= 10.11.0 < 10.11.23)
• mattermost mattermost server (>= 11.7.0 < 11.7.9)
• mattermost mattermost server (>= 11.8.0 < 11.8.5)
• mattermost mattermost server (>= 11.9.0 < 11.9.1)
Related
Weakness · CWE (1)
- CWE-407 Inefficient Algorithmic Complexity weakness
References
- https://mattermost.com/security-updates Vendor Advisory