CVE-2026-33425 Discourse has inferable private group membership or existence via exclude_groups parameter
Unauthenticated attackers can infer private group membership by observing directory results, exposing sensitive user data.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-33425?
CVE-2026-33425 is a medium-severity vulnerability in Discourse Discourse, published on 20 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Which versions are affected by CVE-2026-33425?
1 open source package ship an affected version, including discourse. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
discourse Bitnami | From 2026.1.0 | 2026.1.2, 2026.2.1, 2026.3.0 |
Products include Discourse Discourse.
How do I fix CVE-2026-33425?
Upgrade discourse to a fixed version for your release line: 2026.1.2, 2026.2.1 or 2026.3.0.
Is CVE-2026-33425 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33425 exists.
Public exploit code: 1 Nuclei template.
Other vulnerabilities in Discourse Discourse
- CVE-2021-41163 RCE via malicious SNS subscription payload
- CVE-2022-36066 Discourse vulnerable to RCE via admins uploading maliciously zipped file
- CVE-2022-39356 Discourse user account takeover via email and invite link
- CVE-2023-22468 Discourse vulnerable to Cross-site Scripting in local oneboxes
- CVE-2026-27934 Discourse leaks private topic title and post excerpt via user action API endpoint
Sources
Also known as BIT-discourse-2026-33425, GHSA-r6rh-xvf5-r5f2.