CVE-2026-2454

MEDIUM

DoS in Calls plugin via malformed msgpack in websocket request.

Title source: cna
STIX 2.1

Description

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to handle incorrectly reported array lengths which allows malicious user to cause OOM errors and crash the server via sending corrupted msgpack frames within websocket messages to calls plugin. Mattermost Advisory ID: MMSA-2025-00537

References (1)

Core 1
Core References
Vendor Advisory vendor-advisory
MMSA-2025-00537
https://mattermost.com/security-updates

Scores

CVSS v3 5.8
EPSS 0.0013
EPSS Percentile 31.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-1287
Status published
Products (8)
Mattermost/Mattermost 10.11.0 - 10.11.10
Mattermost/Mattermost 10.11.11
Mattermost/Mattermost 11.2.0 - 11.2.2
Mattermost/Mattermost 11.2.3
Mattermost/Mattermost 11.3.0
Mattermost/Mattermost 11.3.1
Mattermost/Mattermost 11.4.0
mattermost/mattermost_server 10.11.0 - 10.11.11
Published Mar 16, 2026
Tracked Since Mar 17, 2026