VulnerabilityAnalyzed

CVE-2026-33425

Discourse is an open-source discussion platform.

MEDIUM 6.9EPSS 0.21%

Does this matter?

Lower severity and a low EPSS score (0.21%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 4.0: 6.9 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.21% probability · 11th percentile
CISA KEV: Not listed
Weakness: CWE-203, CWE-639, CWE-862
Affected: discourse/discourse
Source: security-advisories@github.com

References

https://github.com/discourse/discourse/security/advisories/GHSA-r6rh-xvf5-r5f2Mitigation, Vendor Advisory

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.