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 frameworks $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.
Weakness
The product downloads source code or an executable from a remote location and executes the code without sufficiently verifying the origin and integrity of the code.
Potential Mitigations
Encrypt the code with a reliable encryption scheme before transmitting.
This will only be a partial solution, since it will not detect DNS spoofing and it will not prevent your code from being modified on the hosting site.
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482].
Speficially, it may be helpful to use tools or frameworks to perform integrity checking on the transmitted code.
Run the code in a “jail” or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.
This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.
Be careful to avoid CWE-243 and other weaknesses related to jails.
Related Attack Patterns
- https://cwe.mitre.org/data/definitions/184.html
- https://cwe.mitre.org/data/definitions/185.html
- https://cwe.mitre.org/data/definitions/186.html
- https://cwe.mitre.org/data/definitions/187.html
- https://cwe.mitre.org/data/definitions/533.html
- https://cwe.mitre.org/data/definitions/538.html
- https://cwe.mitre.org/data/definitions/657.html
- https://cwe.mitre.org/data/definitions/662.html
- https://cwe.mitre.org/data/definitions/691.html
- https://cwe.mitre.org/data/definitions/692.html
- https://cwe.mitre.org/data/definitions/693.html
- https://cwe.mitre.org/data/definitions/695.html