CVE-2026-86349
EUVD-2026-7748014.09.2026, 14:17
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-2026-00707Enginsight
Affected Products (NVD)
| Vendor | Product | Version |
|---|---|---|
| mattermost | mattermost_server | 10.11.0 ≤ 𝑥 < 10.11.23 |
| mattermost | mattermost_server | 11.7.0 ≤ 𝑥 < 11.7.9 |
| mattermost | mattermost_server | 11.8.0 ≤ 𝑥 < 11.8.5 |
| mattermost | mattermost_server | 11.9.0 ≤ 𝑥 < 11.9.1 |
𝑥
= Vulnerable software versions
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources
(CNA/ADP records, vendor advisories, Enginsight analysis).
| Vendor | Product | Version | Source |
|---|---|---|---|
| mattermost | mattermost | 11.9.0 | CNA |
| mattermost | mattermost | 11.8.0 ≤ 𝑥 ≤ 11.8.4 | CNA |
| mattermost | mattermost | 11.7.0 ≤ 𝑥 ≤ 11.7.8 | CNA |
| mattermost | mattermost | 10.11.0 ≤ 𝑥 ≤ 10.11.22 | CNA |
References