CVE-2026-46386: Opf Openproject

Critical severity, CVSS 9.9. EPSS: 0.5% chance of exploitation in the next 30 days.

OpenProject is open-source, web-based project management software. Prior to , the official openproject/openproject Docker image ships ENV SECRET_KEY_BASE=OVERWRITE_ME as the default Rails master key. Combined with cookies_serializer = :marshal, this gives any logged-in user a deterministic Marshal-deserialization path reachable via the /my/two_factor_devices cookie reader This vulnerability is fixed in .

Affected products

• Opf Openproject: from 8.3.0, before 17.2.4 (fixed in 17.2.4); from 17.3.0, before 17.3.2 (fixed in 17.3.2)

Published 2026-06-26. Last modified 2026-06-29.