CVE-2025-66488

Discourse is an open source discussion platform. A vulnerability present in versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 affects anyone who uses S3 for uploads. While scripts may be executed, they will only be run in the context of the S3/CDN domain, with no site credentials. Versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 fix the issue. As a workaround, disallow html or xml files for uploads in authorized_extensions. For existing html xml uploads, site owners can consider deleting them.

CVSS v3 4.6 MEDIUM

4.6^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.1 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/discourse/discourse/security/advisories/GHSA-68jp-3934-62rx	Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:discourse:discourse:::::stable:::*
	cpe:2.3:a:discourse:discourse:::::stable:::*
	cpe:2.3:a:discourse:discourse:2025.12.0::::stable:::
	cpe:2.3:a:discourse:discourse:2026.1.0::::stable:::

History

30 Jan 2026, 20:31

Type	Values Removed	Values Added
CPE		cpe:2.3:a:discourse:discourse:2026.1.0::::stable::: cpe:2.3:a:discourse:discourse:::::stable:::* cpe:2.3:a:discourse:discourse:2025.12.0::::stable:::
First Time		Discourse Discourse discourse
References	~~() https://github.com/discourse/discourse/security/advisories/GHSA-68jp-3934-62rx -~~	() https://github.com/discourse/discourse/security/advisories/GHSA-68jp-3934-62rx - Third Party Advisory

28 Jan 2026, 19:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-01-28 19:16

Updated : 2026-01-30 20:31

NVD link : CVE-2025-66488

Mitre link : CVE-2025-66488

CVE.ORG link : CVE-2025-66488

JSON object : View

Products Affected

discourse

discourse

CWE

CWE-116

Improper Encoding or Escaping of Output

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