CVE-2026-33425

MEDIUM

Discourse has inferable private group membership or existence via exclude_groups parameter

Title source: cna
STIX 2.1

Description

Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, unauthenticated users can determine whether a specific user is a member of a private group by observing changes in directory results when using the `exclude_groups` parameter. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. As a workaround, disable public access to the user directory via Admin → Settings → hide user profiles from public.

References (1)

Core 1
Core References

Scores

CVSS v3 5.3
EPSS 0.0021
EPSS Percentile 10.7%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-203 CWE-639 CWE-862
Status published
Products (5)
discourse/discourse 2026.3.0
discourse/discourse 2026.1.0 - 2026.1.2
discourse/discourse = 2026.3.0-latest
discourse/discourse >= 2026.1.0-latest, < 2026.1.2
discourse/discourse >= 2026.2.0-latest, < 2026.2.1
Published Mar 21, 2026
Tracked Since Mar 21, 2026