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
Metrics
Affected Vendors & Products
References
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| https://mattermost.com/security-updates |
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History
Wed, 07 Oct 2026 18:15:00 +0000
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| CPEs | cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* | |
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Mattermost mattermost Server
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Mon, 14 Sep 2026 21:00:00 +0000
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ssvc
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Mon, 14 Sep 2026 14:00:00 +0000
| Type | Values Removed | Values Added |
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| 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 | |
| Title | Mattermost Server Algorithmic DoS via Unbounded Markdown Block Nesting | |
| Weaknesses | CWE-407 | |
| References |
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| Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: Mattermost
Published: 2026-09-14T13:51:30.175Z
Updated: 2026-09-14T19:23:01.455Z
Reserved: 2026-09-07T09:38:22.768Z
Link: CVE-2026-86349
Updated: 2026-09-14T19:15:30.809Z
Status : Analyzed
Published: 2026-09-14T14:17:15.687
Modified: 2026-10-07T17:59:29.997
Link: CVE-2026-86349
No data.