CVE-2026-6850
EUVD-2026-4331313.07.2026, 09:16
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to validate the length and content of message attachment field values, which allows an authenticated attacker to cause a denial of service for all users in a channel via a post containing a specially crafted payload that triggers catastrophic backtracking in the client-side markdown parser.. Mattermost Advisory ID: MMSA-2026-00658Enginsight
Affected Products (NVD)
| Vendor | Product | Version |
|---|---|---|
| mattermost | mattermost_server | 10.11.0 ≤ 𝑥 < 10.11.20 |
| mattermost | mattermost_server | 11.6.0 ≤ 𝑥 < 11.6.5 |
| mattermost | mattermost_server | 11.7.0 ≤ 𝑥 < 11.7.3 |
𝑥
= Vulnerable software versions
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
| Vendor | Product | Version | Source |
|---|---|---|---|
| mattermost | mattermost | 11.7.0 ≤ 𝑥 ≤ 11.7.2 | CNA |
| mattermost | mattermost | 11.6.0 ≤ 𝑥 ≤ 11.6.4 | CNA |
| mattermost | mattermost | 10.11.0 ≤ 𝑥 ≤ 10.11.19 | CNA |
Common Weakness Enumeration
References