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

published 2026-06-26 4 mo ago modified 2026-10-25 14 d ago also EUVD-2026-39875

cvss: 9.9; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 42%
public exploits: 0; none known

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 .

Patch / fix

fixed in 1

openproject openproject 17.2.4, 17.3.2

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 4 mo ago (2026-06-29)

Exploit prediction

0.49% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	9.9	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Affected products

opf openproject

Classification

Weakness

CWE-502 Deserialization of Untrusted Data
CWE-798 Use of Hard-coded Credentials
CWE-1188 Initialization of a Resource with an Insecure Default
CWE-1392 Use of Default Credentials

References

github.com /opf/openproject/security/advisories/GHSA-r85r-gjq2-f83r

Sources

CVE List CVE-2026-46386
NVD CVE-2026-46386

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.

Summary