GHSA-hqpj-f3jh-29vxLowCVSS 3.7

Mattermost doesn't validate that the RefreshedToken differs from the original invite token during remote cluster invite confirmation

Published
May 18, 2026
Last Modified
June 1, 2026

🔗 CVE IDs covered (1)

CVE-2026-4273 →

📋 Description

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to validate that the RefreshedToken differs from the original invite token during remote cluster invite confirmation which allows an authenticated attacker to bypass token rotation and reuse the original invite token via sending a crafted invite confirmation with a RefreshedToken matching the original token. Mattermost Advisory ID: MMSA-2026-00575

🎯 Affected products4

  • go/github.com/mattermost/mattermost/server/v8:>= 11.5.0, < 11.5.2
  • go/github.com/mattermost/mattermost/server/v8:>= 10.11.0, < 10.11.14
  • go/github.com/mattermost/mattermost/server/v8:< 8.0.0-20260313190740-742e0be95074
  • go/github.com/mattermost/mattermost-server:< 5.3.2-0.20260313190740-742e0be95074

🔗 References (4)