CVE-2023-45847: Mattermost Server

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

Mattermost fails to to check the length when setting the title in a run checklist in Playbooks, allowing an attacker to send a specially crafted request and crash the Playbooks plugin

Affected products

• Mattermost Mattermost Server: up to and including 7.8.14; from 8.0.0, up to and including 8.1.5; from 9.0.0, up to and including 9.0.3; from 9.1.1, up to and including 9.1.2; from 9.2.0, up to and including 9.2.1

Published 2023-12-12. Last modified 2026-06-17.