Vulnerability · Published Mar 19, 2026 · Assigned by GitHub_M

CVE-2026-27934Discourse leaks private topic title and post excerpt via user action API endpoint

High 8.7

In plain English

A high-severity security flaw in discourse from discourse. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.2% (higher than 69% of all known vulnerabilities). Ready-made attack tooling exists: Nuclei.

Severity (CVSS 4.0)8.7High

Exploit odds (30 days)1.2%top 31.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack tooling1Nuclei

Official 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.

Affected products (as reported)

Vendor	Product	Versions
discourse	discourse	>= 2026.1.0-latest, < 2026.1.2>= 2026.2.0-latest, < 2026.2.1= 2026.3.0-latest

Weakness: CWE-201 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

References

https://github.com/discourse/discourse/security/advisories/GHSA-824f-66wh-xx3g x_refsource_CONFIRM