High severity7.5NVD Advisory· Published Jul 9, 2026· Updated Jul 14, 2026
CVE-2026-55420
CVE-2026-55420
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
4cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*+ 2 more
- cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*range: >=2026.1.0,<2026.1.5
- cpe:2.3:a:discourse:discourse:2026.6.0:*:*:*:latest:*:*:*
- (no CPE)range: <2026.6.0, <2026.5.1, <2026.4.2, <2026.1.5
Patches
Vulnerability mechanics
References
6- github.com/discourse/discourse/commit/ca5a7e06167561928556afa2f237d67e459c6914nvdPatch
- github.com/discourse/discourse/security/advisories/GHSA-7wq5-jgww-5rw3nvdMitigationVendor Advisory
- github.com/discourse/discourse/releases/tag/v2026.1.5nvdRelease Notes
- github.com/discourse/discourse/releases/tag/v2026.4.2nvdRelease Notes
- github.com/discourse/discourse/releases/tag/v2026.5.1nvdRelease Notes
- github.com/discourse/discourse/releases/tag/v2026.6.0nvdRelease Notes
News mentions
1- Discourse Image Pipeline Exploit Chains JPEG Race, GhostScript and ImageMagick for File ReadCyber Security News · Oct 12, 2026