CVE-2026-28227 (GCVE-0-2026-28227)

Vulnerability from cvelistv5 – Published: 2026-02-26 21:27 – Updated: 2026-03-03 14:44
VLAI
Title
Discourse Vulnerable to Unauthorized Topic Creation in Staff-Only Categories via Topic Timer publish_to_category
Summary
Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, TL4 users can publish topics into staff-only categories via the `publish_to_category` topic timer, bypassing authorization checks. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available.
Severity
1.2 (Low)
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-03 14:44 UTC
CWE
  • CWE-863 - Incorrect Authorization
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7761 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
discourse discourse Affected: < 2025.12.2
Affected: >= 2026.1.0-latest, < 2026.1.1
Affected: >= 2026.2.0-latest, < 2026.2.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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