4.6
/ 10
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:L
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.
Basic Information
ID
CVE-2025-66488
Source
GitHub_M
Published
Jan 28, 2026 at 18:15
Modified
Jan 28, 2026 at 18:28
Affected Product
Vendor
discourse
Product
discourse
Version
< 3.5.4
Affected Versions
discourse discourse < 3.5.4
discourse discourse >= 2025.11.0-latest, < 2025.11.2
discourse discourse >= 2025.12.0-latest, 2025.12.1
discourse discourse >= 2026.1.0-latest, < 2026.1.0
discourse discourse >= 2025.11.0-latest, < 2025.11.2
discourse discourse >= 2025.12.0-latest, 2025.12.1
discourse discourse >= 2026.1.0-latest, < 2026.1.0