Vulnerability in Mjdm Majordomo

CVE-2026-27180

MajorDoMo (aka Major Domestic Module) is vulnerable to unauthenticated remote code execution through supply chain compromise via update URL poisoning. The saverestore module exposes its admin() method through the /objects/?module=saverestore endpoint without authentication because it uses gr('mode') (which reads directly from $_REQUEST) instead of the framework's $this->mode. An attacker can poison the system update URL via the auto_update_settings mode handler, then trigger the force_update handler to initiate the update chain. The autoUpdateSystem() method fetches an Atom feed from the attacker-controlled URL with trivial validation, downloads a tarball via curl with TLS verification disabled (CURLOPT_SSL_VERIFYPEER set to FALSE), extracts it using exec('tar xzvf ...'), and copies all extracted files to the document root using copyTree(). This allows an attacker to deploy arbitrary PHP files, including webshells, to the webroot with two GET requests.

EPSS: 0.011 (61.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2026-27180?
CVE-2026-27180 is a critical-severity vulnerability in Mjdm Majordomo, classified under Download of Code Without Integrity Check. CVSS score: 9.8/10. Published 2026-02-18.
How severe is CVE-2026-27180?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2026-27180 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.