CVE-2023-5330: Mattermost Server

High severity, CVSS 7.5. EPSS: 0.6% chance of exploitation in the next 30 days.

Mattermost fails to enforce a limit for the size of the cache entry for OpenGraph data allowing an attacker to send a specially crafted request to the /api/v4/opengraph filling the cache and turning the server unavailable.

Affected products

• Mattermost Mattermost Server: before 7.8.11 (fixed in 7.8.11); from 8.0.0, before 8.0.3 (fixed in 8.0.3); from 8.1.0, before 8.1.2 (fixed in 8.1.2)

Published 2023-10-09. Last modified 2026-06-17.