Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, TL4 users are able to close, archive and pin topics in private categories they don't have access to. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue.
No known workarounds are available.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
High
Admin privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
None
No disruption
CVSS Vector v4.0