Unauthorized access to invite ID during team creation

Summary

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to filter invite IDs based on user permissions, which allows regular users to bypass access control restrictions and register unauthorized accounts via leaked invite IDs during team creation.. Mattermost Advisory ID: MMSA-2025-00565

Timeline

1. Mar 16, 2026, 11:13 AM UTCCVE published
2. Mar 16, 2026, 1:42 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: partial

3. Mar 16, 2026, 1:49 PM UTCRecord last updated

Affected versions

• Mattermost Mattermost

  From 11.3.0 · through 11.3.0; From 11.2.0 · through 11.2.2; From 10.11.0 · through 10.11.10

• github.com/mattermost/mattermost-serverGo

  From 10.11.0-rc1+incompatible · fixed in 10.11.11+incompatible; From 11.2.0-rc1+incompatible · fixed in 11.2.3+incompatible; From 11.3.0-rc1+incompatible · fixed in 11.3.1+incompatible

• github.com/mattermost/mattermost-server/v5Go

  All versions

• github.com/mattermost/mattermost-server/v6Go

  All versions

• github.com/mattermost/mattermost/server/v8Go

  fixed in 8.0.0-20260105134819-cc427af41b2a

• github.com/mattermost/mattermost-serverGo

  fixed in 5.3.2-0.20260105134819-cc427af41b2a

• github.com/mattermost/mattermost-serverGo

  From 10.11.0-rc1 · fixed in 10.11.11

• github.com/mattermost/mattermost-serverGo

  From 11.2.0-rc1 · fixed in 11.2.3

• github.com/mattermost/mattermost-serverGo

  From 11.3.0-rc1 · fixed in 11.3.1

References 1