CVE-2026-21865 (GCVE-0-2026-21865)

Vulnerability from cvelistv5 – Published: 2026-01-28 19:51 – Updated: 2026-01-28 20:10
VLAI
Title
Discourse topic conversion permission vulnerability for moderators
Summary
Discourse is an open source discussion platform. In versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0, moderators can convert some personal messages to public topics when they shouldn't have access. This issue is patched in versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0. As a workaround, site admin can temporarily revoke the moderation role from untrusted moderators or remove the moderator group from the "personal message enabled groups" site setting until the Discourse instance has been upgraded to a version that has been patched.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-28 20:09 UTC
CWE
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7926 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
discourse discourse Affected: < 3.5.4
Affected: >= 2025.11.0-latest, < 2025.11.2
Affected: >= 2025.12.0-latest, < 2025.12.1
Affected: >= 2026.1.0-latest, < 2026.1.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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