# CVE-2026-27934: Discourse - Information Disclosure

> Live exploitation tracking for CVE-2026-27934 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-2026-27934

## Key facts

- **Exploitation phase:** Limited Exploitation. The vulnerability is known but shows very limited attacker interest or exploitation activity.
- **CVSS score:** 8.7
- **Public exploit available:** Yes
- **Affected products:** Discourse
- **Weaknesses:** CWE-201 (Insertion of Sensitive Information Into Sent Data)
- **Tags:** forum

## Description

Discourse is an open-source discussion platform. Versions prior to 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 have a lack of visibility checks with a user action API endpoint that results in disclosure of the title and post excerpt to unauthorized users, leading to information disclosure. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. No known workarounds are available.

## CrowdSec analysis

[CVE-2026-27934](https://euvd.enisa.europa.eu/vulnerability/CVE-2026-27934) is an information disclosure vulnerability in Discourse caused by missing visibility checks in a user action API endpoint. Unauthenticated remote attackers may access discussion titles and post excerpts that should be restricted, potentially exposing sensitive content; upgrade to a patched version (2026.1.2, 2026.2.1, or 2026.3.0-latest.1) to address the flaw.

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

CrowdSec has not observed any significant exploitation activity targeting CVE-2026-27934 across its network. As a result, no community-driven trend analysis is available for this vulnerability at this time.

Attackers target `/user_actions/{id}.json` with numeric user-action IDs to access action data without authentication. Successful exploitation can disclose private post titles and excerpts.

## Timeline

- 2026-03-19: CVE Published. CVE-2026-27934 is published to NVD.
- 2026-10-20: Rule Released. CrowdSec releases a rule to detect CVE-2026-27934 exploitation attempts against the CrowdSec Network.
- 2026-10-21: First exploitation attempt seen by CrowdSec

## References

- https://github.com/discourse/discourse/security/advisories/GHSA-824f-66wh-xx3g
- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-27934.yaml

## Live exploitation data

The [Live Exploit Tracker page](https://tracker.crowdsec.net/cves/CVE-2026-27934) follows observed exploitation activity for CVE-2026-27934. [Request an API key](https://tracker.crowdsec.net/request-api-key) for full access to its exploitation timeline, attacking IP addresses and blocklists.