Vulnerability · Published Jun 26, 2026 · Assigned by GitHub_M

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

Critical 9.9

In plain English

A critical-severity unsafe deserialization in openproject from opf. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities).

Severity (CVSS 3.1)9.9Critical
Exploit odds (30 days)0.5%top 57.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

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 (as reported)

VendorProductVersions
opf openproject >= 8.3.0, < 17.2.4>= 17.3.0, < 17.3.2

Weakness: CWE-502, CWE-798, CWE-1188, CWE-1392 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

References