Vulnerability · Published Jul 9, 2026 · Assigned by GitHub_M
CVE-2026-55420Discourse: Remote code execution via pdf uploads
High 7.5
In plain English
A high-severity OS command injection 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 0.6% (higher than 49% of all known vulnerabilities).
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.6%top 51.0% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, under certain non-default configurations, processing of PDF uploads could be exploited to obtain RCE on the server. This issue is patched in 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.
Affected products (as reported)
Weakness: CWE-78 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
References
- https://github.com/discourse/discourse/security/advisories/GHSA-7wq5-jgww-5rw3 x_refsource_CONFIRM
- https://github.com/discourse/discourse/commit/ca5a7e06167561928556afa2f237d67e459c6914 x_refsource_MISC
- https://github.com/discourse/discourse/releases/tag/v2026.1.5 x_refsource_MISC
- https://github.com/discourse/discourse/releases/tag/v2026.4.2 x_refsource_MISC
- https://github.com/discourse/discourse/releases/tag/v2026.5.1 x_refsource_MISC
- https://github.com/discourse/discourse/releases/tag/v2026.6.0 x_refsource_MISC