CVE-2026-49256

HIGH7.5

Discourse: Hidden tag names leaked via category serializers

Published Jul 9, 2026

Modified 5 days ago

Details

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, restricted tag and tag-group names attached to publicly readable categories as allowed_tags, allowed_tag_groups, or required tag groups could leak to anonymous and unauthorized users through category and group endpoints. This issue is fixed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.

References

WEB

https://github.com/discourse/discourse/releases/tag/v2026.1.5

WEB

https://github.com/discourse/discourse/releases/tag/v2026.4.2

WEB

https://github.com/discourse/discourse/releases/tag/v2026.5.1

WEB

https://github.com/discourse/discourse/releases/tag/v2026.6.0

WEB

https://github.com/discourse/discourse/security/advisories/GHSA-mwp7-572g-6qpx

ADVISORY