CVE-2026-28219

Medium

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.

SeverityMedium
CVSS4.3
Exploit probability—
ProductDiscourse
PublishedFeb 26, 2026
First seenFeb 26, 2026
Weakness typeCWE-915CWE-915

How to fix

Update
  • discourse discourse2025.12.2, 2026.1.1 or later

Affected products

ProductAffected versionsFixed in
discourse discoursev < 2025.12.2, 2026.1.0 ≤ v < 2026.1.1, 2026.2.02025.12.2, 2026.1.1

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