CVE-2026-27180: Mjdm Majordomo remote code execution (CVSS 9.8)

Description

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.

CVSS 3.1 breakdown

Attack vectorNetwork

Attack complexityLow

Privileges requiredNone

User interactionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

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

Affected products

Mjdm Majordomoall versions

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

References

https://chocapikk.com/posts/2026/majordomo-revisited/ExploitThird Party Advisory
https://github.com/sergejey/majordomo/pull/1177ExploitIssue Tracking
https://www.vulncheck.com/advisories/majordomo-supply-chain-remote-code-execution-via-update-url-poisoningThird Party Advisory

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

Frequently asked

Is CVE-2026-27180 being actively exploited?

CVE-2026-27180 is not in the CISA KEV catalog. A public exploit reference exists, so treat it as exploitable. Its EPSS exploit probability is 1.15%.

How severe is CVE-2026-27180?

CVE-2026-27180 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 1.15% probability of exploitation.

Which products are affected by CVE-2026-27180?

Affected products include Mjdm Majordomo.

How do I fix CVE-2026-27180?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-27180 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

See how prioritisation works Book a demo