CVE-2026-55420

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.6 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/discourse/discourse/commit/ca5a7e06167561928556afa2f237d67e459c6914	Patch
https://github.com/discourse/discourse/releases/tag/v2026.1.5	Release Notes
https://github.com/discourse/discourse/releases/tag/v2026.4.2	Release Notes
https://github.com/discourse/discourse/releases/tag/v2026.5.1	Release Notes
https://github.com/discourse/discourse/releases/tag/v2026.6.0	Release Notes
https://github.com/discourse/discourse/security/advisories/GHSA-7wq5-jgww-5rw3	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse:2026.6.0::::latest:::

History

No history.

Information

Published : 2026-07-09 18:16

Updated : 2026-07-14 02:16

NVD link : CVE-2026-55420

Mitre link : CVE-2026-55420

CVE.ORG link : CVE-2026-55420

JSON object : View

Products Affected

discourse

discourse

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

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