GHSA-86vc-mg26-fj6xMediumCVSS 4.3

Mattermost: Authenticated DoS through failure to prevent rendering of external SVGs on link embeds

Published
March 25, 2026
Last Modified
March 30, 2026

🔗 CVE IDs covered (1)

CVE-2026-20719 →

📋 Description

Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to prevent rendering of external SVGs on link embeds which allows unauthenticated users to crash the Mattermost webapp and desktop app via creating an issue or PR on GitHub. Mattermost Advisory ID: MMSA-2026-00595

🎯 Affected products5

  • go/github.com/mattermost/mattermost/server/v8:>= 11.4.0-rc1, < 11.4.1
  • go/github.com/mattermost/mattermost/server/v8:>= 11.3.0-rc1, < 11.3.2
  • go/github.com/mattermost/mattermost/server/v8:>= 11.2.0-rc1, < 11.2.4
  • go/github.com/mattermost/mattermost/server/v8:>= 8.0.0-20260105080200-d27a2195068d, < 8.0.0-20260217110922-b7d4a1f1f59b
  • go/github.com/mattermost/mattermost/server/v8:>= 10.11.0-rc1, < 10.11.2

🔗 References (3)