The Ultimate Store Kit Elementor Addons, Woocommerce Builder, EDD Builder, Elementor Store Builder, Product Grid, Product Table, Woocommerce Slider plugin is vulnerable to PHP Object Injection via deserialization of untrusted input via the _ultimate_store_kit_compare_products cookie in versions up to , and including, 1.6.4. This makes it possible for an unauthenticated attacker to inject a PHP Object.
No POP chain is present in the vulnerable plugin. If a POP chain is present via an additional plugin or theme installed on the target system, it could allow the attacker or above to delete arbitrary files, retrieve sensitive data, or execute code.
The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid.
It is often convenient to serialize objects for communication or to save them for later use. However, deserialized data or code can often be modified without using the provided accessor functions if it does not use cryptography to protect itself. Furthermore, any cryptography would still be client-side security – which is a dangerous security assumption. Data that is untrusted can not be trusted to be well-formed. When developers place no restrictions on “gadget chains,” or series of instances and method invocations that can self-execute during the deserialization process (i.e., before the object is returned to the caller), it is sometimes possible for attackers to leverage them to perform unauthorized actions, like generating a shell.