Medium severity · published Feb 26, 2026
CVE-2026-28219
Privilege Escalation via Mass Assignment Allows Regular Users to Set Topics as Global Banners
4.3
CVSS
0.2%
EPSS
No
On KEV
Description
Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, an improper authorization check in the topic management logic allows authenticated users to modify privileged attributes of their topics. By manipulating specific parameters in a PUT or POST request, a regular user can elevate a topic’s status to a site-wide notice or banner, bypassing intended administrative restrictions. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. There are no practical workarounds to prevent this behavior other than applying the security patch. Administrators concerned about unauthorized promotions should audit recent changes to site banners and global notices until the fix is deployed.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 14% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DI
discourse · discourse
< 2025.12.2; >= 2026.1.0-latest, < 2026.1.1; >= 2026.2.0-latest, < 2026.2.0 · source: vendor, NVD
Affected product
DI
discourse
discourse
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