CVE-2026-46386 CRITICAL

CVE-2026-46386: OpenProject: Pre-authentication RCE in openproject/openproject Docker image via default `SECRET_KEY_BASE=OVERWRITE_ME` and `cookies_serializer = :marshal`

Vendor Opf
Product openproject
Weakness CWE-502 · Unsafe deserialization
Published June 26, 2026
Last update June 29, 2026
View on NVD All CVEs

CVSS base score

9.9/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

What the vulnerability does

01Description

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 .

Key dates

02Disclosure timeline

June 26, 2026 CVE published
June 29, 2026 Record updated