CVE-2026-96260
published 2026-09-22CVE-2026-96260: Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to enforce a request body size limit during CSRF validation…
PriorityP337medium6.5CVSS 3.1
AVNACLPRLUINSUCNINAH
EPSS
0.42%
35.2th percentile
Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to enforce a request body size limit during CSRF validation of plugin requests which allows an authenticated user to exhaust server memory and cause a denial of service via a large request body sent to a plugin endpoint.. Mattermost Advisory ID: MMSA-2026-00775
Affected
8 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mattermost | mattermost | 11.10.0 – 11.10.1 | — |
| mattermost | mattermost | 11.7.0 – 11.7.10 | — |
| mattermost | mattermost | 11.8.0 – 11.8.5 | — |
| mattermost | mattermost | 11.9.0 – 11.9.1 | — |
| mattermost | mattermost_server | >= 11.10.0 < 11.10.2 | 11.10.2 |
| mattermost | mattermost_server | >= 11.7.0 < 11.7.11 | 11.7.11 |
| mattermost | mattermost_server | >= 11.8.0 < 11.8.6 | 11.8.6 |
| mattermost | mattermost_server | >= 11.9.0 < 11.9.2 | 11.9.2 |
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VulDB
Mattermost up to 11.7.10/11.8.5/11.9.1/11.10.1 CSRF validation input validation
vuldb·2026-09-22·CVSS 6.5
CVE-2026-96260 [MEDIUM] Mattermost up to 11.7.10/11.8.5/11.9.1/11.10.1 CSRF validation input validation
A vulnerability was found in Mattermost up to 11.7.10/11.8.5/11.9.1/11.10.1. It has been rated as problematic. Affected is an unknown function of the component CSRF validation. The manipulation leads to improper input validation.
This vulnerability is uniquely identified as CVE-2026-96260. The attack is possible to be carried out remotely. No exploit exists.
Upgrading the affected component is advised.
GHSA
Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to enforce a request body size limit during CSRF validation of plugin requests which allows an authen
ghsa_unreviewed·2026-09-22
CVE-2026-96260 [MEDIUM] CWE-789 Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to enforce a request body size limit during CSRF validation of plugin requests which allows an authen
Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to enforce a request body size limit during CSRF validation of plugin requests which allows an authenticated user to exhaust server memory and cause a denial of service via a large request body sent to a plugin endpoint.. Mattermost Advisory ID: MMSA-2026-00775
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-09-22
Published