CVE-2026-27150: Discourse

Low severity, CVSS 3.8. EPSS: 0.3% chance of exploitation in the next 30 days.

Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, missing `validate_before_create` authorization in Data Explorer's `QueryGroupBookmarkable` allows any logged-in user to create bookmarks for query groups they don't have access to, enabling metadata disclosure via bookmark reminder notifications. Versions 2025.12.2, 2026.1.1, and 2026.2.0 fix this issue and also make sure `validate_before_create` throws NotImplementedError in BaseBookmarkable if not implemented, to prevent similar issues in the future. No known workarounds are available.

Affected products

• Discourse Discourse: before 2025.12.2 (fixed in 2025.12.2); from 2026.1.0, before 2026.1.1 (fixed in 2026.1.1); version 2026.2.0 only

Published 2026-02-26. Last modified 2026-06-17.