CVE-2022-2438

The Broken Link Checker plugin for WordPress is vulnerable to deserialization of untrusted input via the $log_file value in versions up to, and including 1.11.16. This makes it possible for authenticated attackers with administrative privileges and above to call files using a PHAR wrapper that will deserialize the data and call arbitrary PHP Objects that can be used to perform a variety of malicious actions granted a POP chain is also present. It also requires that the attacker is successful in uploading a file with the serialized payload.

Weakness

The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

Affected Software

Potential Mitigations

• Make fields transient to protect them from deserialization.
• An attempt to serialize and then deserialize a class containing transient fields will result in NULLs where the transient data should be. This is an excellent way to prevent time, environment-based, or sensitive variables from being carried over and used improperly.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/586.html

References

• https://plugins.trac.wordpress.org/changeset/2757773/broken-link-checker/trunk/core/core.php?old=2605914\u0026old_path=broken-link-checker%2Ftrunk%2Fcore%2Fcore.php
• https://www.wordfence.com/threat-intel/vulnerabilities/id/62fd472e-208b-48db-8f98-3d935c7a678c?source=cve
• https://www.wordfence.com/vulnerability-advisories/#CVE-2022-2438
• https://plugins.trac.wordpress.org/changeset/2757773/broken-link-checker/trunk/core/core.php?old=2605914\u0026old_path=broken-link-checker%2Ftrunk%2Fcore%2Fcore.php
• https://www.wordfence.com/threat-intel/vulnerabilities/id/62fd472e-208b-48db-8f98-3d935c7a678c?source=cve
• https://www.wordfence.com/vulnerability-advisories/#CVE-2022-2438