CVE-2026-55420
Discourse: Remote code execution via pdf uploads
CVSS Score
7.5
EPSS Score
0.3%
EPSS Percentile
25th
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.
| CWE | CWE-78 |
| Vendor | discourse |
| Product | discourse |
| Published | Jul 9, 2026 |
| Last Updated | Jul 14, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H Attack Vector
Network
Attack Complexity
High
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Affected Versions
discourse / discourse
>= 2026.5.0-latest, < 2026.5.1 >= 2026.4.0-latest, < 2026.4.2 >= 2026.1.0-latest, < 2026.1.5
References
github.com: https://github.com/discourse/discourse/security/advisories/GHSA-7wq5-jgww-5rw3 github.com: https://github.com/discourse/discourse/commit/ca5a7e06167561928556afa2f237d67e459c6914 github.com: https://github.com/discourse/discourse/releases/tag/v2026.1.5 github.com: https://github.com/discourse/discourse/releases/tag/v2026.4.2 github.com: https://github.com/discourse/discourse/releases/tag/v2026.5.1 github.com: https://github.com/discourse/discourse/releases/tag/v2026.6.0