CVE-2021-24384

The joomsport_md_load AJAX action of the JoomSport WordPress plugin before 5.1.8, registered for both unauthenticated and unauthenticated users, unserialised user input from the shattr POST parameter, leading to a PHP Object Injection issue. Even though the plugin does not have a suitable gadget chain to exploit this, other installed plugins could, which might lead to more severe issues such as RCE

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://wpscan.com/vulnerability/fb6c407c-713c-4e83-92ce-4e5f791be696
• https://wpscan.com/vulnerability/fb6c407c-713c-4e83-92ce-4e5f791be696