CVE Database
/

CVE-2026-21865

Back to search

CVE-2026-21865

Published: Jan 28, 2026

Modified: Jan 28, 2026

PUBLISHED

CVSS v3.1

6.5

MEDIUM

Description

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.

VendorProductVersions

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

Weaknesses (CWE)

CVSS v3.1 Details

CVSS v3.1 Vector

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

High

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

None

Security Training

Train your team to recognize and prevent security threats with our comprehensive security awareness program.

Start Training

Vulnerability Scanning

Discover vulnerabilities in your applications and infrastructure before attackers do.

Scan Now