CVE-2025-66488
Published: Jan 28, 2026
Modified: Jan 28, 2026
CVSS v3.1
4.6
Description
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.
| Vendor | Product | Versions |
|---|---|---|
discourse | discourse | affected < 3.5.4affected >= 2025.11.0-latest, < 2025.11.2affected >= 2025.12.0-latest, < 2025.12.1affected >= 2026.1.0-latest, < 2026.1.0 |
Weaknesses (CWE)
CVSS v3.1 Details
CVSS v3.1 Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:L
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
References
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