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CVE-2026-55420

Discourse: Remote code execution via pdf uploads

Published: Jul 9, 2026Updated: Jul 14, 2026 Sources: CVE List NVDCWE-78
7.5HIGH
NVD MITRE
EPSS Score
0.3%
Top 72.5%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:HPR:LUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-78

Affected Products

discourse
commercial·USaka discourse.org
discourse
Web & CMS Plugins

Exploitability

Official Patch Available
Workaround Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Execution
View detailed technique mapping

References

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
and 3 more references View all →

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