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OpenAdvisories
Medium · 6.3 CVE-2026-49256 EUVD-2026-42730

Discourse: Hidden tag names leaked via category serializers

Published Jul 9, 2026 · Updated Jul 10, 2026 · Assigned by GitHub_M

Description

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.

Affected products

VendorProductAffectedFixed
discourse discourse >= 2026.1.0-latest, < 2026.1.5, >= 2026.4.0-latest, < 2026.4.2, >= 2026.5.0-latest, < 2026.5.1 —

References