CVE-2023-3615: Mattermost

High severity, CVSS 8.1. EPSS: 0.3% chance of exploitation in the next 30 days.

Mattermost iOS app fails to properly validate the server certificate while initializing the TLS connection allowing a network attacker to intercept the WebSockets connection.

Affected products

• Mattermost Mattermost: before 2.5.1 (fixed in 2.5.1)

Published 2023-07-17. Last modified 2026-06-17.