BIT-discourse-2026-55420: Discourse: Remote code execution via pdf uploads
Discourse, an open-source discussion platform, contains a remote code execution vulnerability related to processing PDF uploads under certain non-default configurations. This vulnerability affects versions prior to 2026.1.5, 2026.4.2, and 2026.5.1 and is patched in these versions. The issue allows an attacker to execute code on the server by exploiting the PDF upload processing. No known exploits in the wild have been reported. The vulnerability is rated as high severity.
AI Analysis
Technical Summary
CVE-2026-55420 is a remote code execution vulnerability in Discourse affecting PDF upload processing under specific non-default configurations. Versions prior to 2026.1.5, 2026.4.2, and 2026.5.1 are vulnerable. The issue is resolved in Discourse versions 2026.1.5, 2026.4.2, and 2026.5.1 and later. This vulnerability allows an attacker to execute arbitrary code on the server by exploiting the way PDF uploads are handled.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to execute arbitrary code on the Discourse server, potentially leading to full system compromise. This could affect the confidentiality, integrity, and availability of the platform and its data. No known active exploitation has been reported.
Mitigation Recommendations
Upgrade Discourse to version 2026.1.5, 2026.4.2, 2026.5.1, or later to apply the official patches that address this vulnerability. Versions prior to these are vulnerable. No additional mitigation steps are indicated by the vendor advisory.
BIT-discourse-2026-55420: Discourse: Remote code execution via pdf uploads
Description
Discourse, an open-source discussion platform, contains a remote code execution vulnerability related to processing PDF uploads under certain non-default configurations. This vulnerability affects versions prior to 2026.1.5, 2026.4.2, and 2026.5.1 and is patched in these versions. The issue allows an attacker to execute code on the server by exploiting the PDF upload processing. No known exploits in the wild have been reported. The vulnerability is rated as high severity.
Affected software
pkg:bitnami/discourseRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-55420 is a remote code execution vulnerability in Discourse affecting PDF upload processing under specific non-default configurations. Versions prior to 2026.1.5, 2026.4.2, and 2026.5.1 are vulnerable. The issue is resolved in Discourse versions 2026.1.5, 2026.4.2, and 2026.5.1 and later. This vulnerability allows an attacker to execute arbitrary code on the server by exploiting the way PDF uploads are handled.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to execute arbitrary code on the Discourse server, potentially leading to full system compromise. This could affect the confidentiality, integrity, and availability of the platform and its data. No known active exploitation has been reported.
Mitigation Recommendations
Upgrade Discourse to version 2026.1.5, 2026.4.2, 2026.5.1, or later to apply the official patches that address this vulnerability. Versions prior to these are vulnerable. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- BIT-discourse-2026-55420
- Osv Schema Version
- 1.6.2
- Aliases
- ["CVE-2026-55420"]
- Ecosystems
- ["Bitnami"]
- Database Specific Severity
- High
- Cvss Version
- null
Threat ID: 6a561c4a68715ace4365a2f3
Added to database: 07/14/2026, 11:23:54 UTC
Last enriched: 07/14/2026, 11:32:34 UTC
Last updated: 07/14/2026, 11:32:34 UTC
Views: 3
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