GHSA-ffpr-pfr4-g354MediumCVSS 4.3

Mattermost doesn't sanitize team member data when returned via API to users without elevated permissions

Published
May 26, 2026
Last Modified
June 26, 2026

🔗 CVE IDs covered (1)

CVE-2026-3636 →

📋 Description

Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to sanitize team member data when returned via API to users without elevated permissions which allows a user without permissions to get data about team members roles via invoking various team API endpoints. Mattermost Advisory ID: MMSA-2026-00626.

🎯 Affected products4

  • go/github.com/mattermost/mattermost-server:= 11.6.0
  • go/github.com/mattermost/mattermost-server:>= 11.5.0, < 11.5.4
  • go/github.com/mattermost/mattermost-server:>= 11.4.0, < 11.4.5
  • go/github.com/mattermost/mattermost-server:>= 10.11.0, < 10.11.15

🔗 References (3)