CVE-2026-27175: MajorDoMo Command Injection in rc/index.php via Race Condition

Is it exploited?

Reported, not confirmed by CISA. VulnCheck KEV lists it as exploited in the wild. CISA has not added it to its Known Exploited Vulnerabilities catalog as of 29 Oct 2026.

VulnCheck KEV lists it since 13 Apr 2026. VulnCheck's own honeypots also recorded exploitation attempts.

How likely is exploitation in the next 30 days?

6.9%

Down from 7.8% on 23 Oct 2026.

EPSS score, percentile 94.1 of all scored records. A probability estimated by FIRST, not a report of exploitation.

CISA's SSVC assessment in the CVE record lists exploitation as poc.

How severe?

9.2 Critical

CVSS v4.0 base score, given by the CNA

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Affected

• unspecified

Versions by product

Source: CISA KEV 2026.10.29, as of 29 Oct 2026; VulnCheck KEV, as of 30 Oct 2026; FIRST EPSS, as of 30 Oct 2026; CVE List, as of 30 Oct 2026. About the data.

Description

MajorDoMo Command Injection in rc/index.php via Race Condition

MajorDoMo (aka Major Domestic Module) is vulnerable to unauthenticated OS command injection via rc/index.php. The $param variable from user input is interpolated into a command string within double quotes without sanitization via escapeshellarg(). The command is inserted into a database queue by safe_exec(), which performs no sanitization. The cycle_execs.php script, which is web-accessible without authentication, retrieves queued commands and passes them directly to exec(). An attacker can exploit a race condition by first triggering cycle_execs.php (which purges the queue and enters a polling loop), then injecting a malicious command via the rc endpoint while the worker is polling. The injected shell metacharacters expand inside double quotes, achieving remote code execution within one second.

Source: CVE List, as of 30 Oct 2026. About the data.

What to do

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

This summary is based on the CVE record as of 30 Oct 2026. Check the vendor's advisory before you act: affected versions and fixes can change.

Affected products and versions

Source: CVE List, as of 30 Oct 2026. About the data.

Timeline