# CVE-2026-33425: Discourse - Information Disclosure

> Live exploitation tracking for CVE-2026-33425 by the CrowdSec Live Exploit Tracker, built from real-world attack data crowdsourced from CrowdSec's global network.

Page: https://tracker.crowdsec.net/cves/CVE-2026-33425

## Key facts

- **Exploitation phase:** Limited Exploitation. The vulnerability is known but shows very limited attacker interest or exploitation activity.
- **CVSS score:** 6.9
- **Public exploit available:** Yes
- **Affected products:** Discourse
- **Weaknesses:** CWE-203 (Observable Discrepancy); CWE-639 (Authorization Bypass Through User-Controlled Key); CWE-862 (Missing Authorization)
- **Tags:** forum

## 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.

## CrowdSec analysis

[CVE-2026-33425](https://euvd.enisa.europa.eu/vulnerability/CVE-2026-33425) is an information disclosure vulnerability in Discourse that allows unauthenticated attackers to infer whether a specific user belongs to a private group by comparing user directory results with the `exclude_groups` parameter. This can expose private group membership, and the issue is fixed in versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2.

CrowdSec has been tracking this vulnerability and its exploits since 20th of October 2026.

CrowdSec has not observed any significant exploitation activity targeting CVE-2026-33425 across its network. As a result, no community-driven trend analysis is available for this vulnerability at this time.

Attackers target Discourse’s `/directory_items.json` endpoint and vary the `exclude_groups` parameter to compare directory results. Changes in the returned results can reveal whether users belong to private groups.

## Timeline

- 2026-03-20: CVE Published. CVE-2026-33425 is published to NVD.
- 2026-10-20: Rule Released. CrowdSec releases a rule to detect CVE-2026-33425 exploitation attempts against the CrowdSec Network.

## References

- https://github.com/discourse/discourse/security/advisories/GHSA-r6rh-xvf5-r5f2
- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-33425.yaml

## Live exploitation data

The [Live Exploit Tracker page](https://tracker.crowdsec.net/cves/CVE-2026-33425) follows observed exploitation activity for CVE-2026-33425. [Request an API key](https://tracker.crowdsec.net/request-api-key) for full access to its exploitation timeline, attacking IP addresses and blocklists.