CVE-2026-27481 (GCVE-0-2026-27481)

Vulnerability from cvelistv5 – Published: 2026-04-03 21:27 – Updated: 2026-04-07 14:18
VLAI
Title
Discourse: Hidden tag visibility bypass on tag routes
Summary
Discourse is an open-source discussion platform. From versions 2026.1.0-latest to before 2026.1.3, 2026.2.0-latest to before 2026.2.2, and 2026.3.0-latest to before 2026.3.0, an authorization bypass vulnerability allows unauthenticated or unauthorized users to view hidden (staff-only) tags and its associated data. All Discourse instances with tagging enabled and staff-only tag groups configured are impacted. This issue has been patched in versions 2026.1.3, 2026.2.2, and 2026.3.0.
Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-07 14:18 UTC
CWE
  • CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
discourse discourse Affected: >= 2026.1.0-latest, < 2026.1.3
Affected: >= 2026.2.0-latest, < 2026.2.2
Affected: >= 2026.3.0-latest, < 2026.3.0
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