CVE-2025-34292

Rox, the software running BeWelcome, contains a PHP object injection vulnerability resulting from deserialization of untrusted data. User-controlled input is passed to PHPs unserialize(): the POST parameter formkit_memory_recovery in RoxPostHandler::getCallbackAction and the memory cookie read by RoxModelBase::getMemoryCookie (bwRemember). (1) If present, formkit_memory_recovery is processed and passed to unserialize(), and (2) restore-from-memory functionality calls unserialize() on the bwRemember cookie value. Gadget chains present in Rox and bundled libraries enable exploitation of object injection to write arbitrary files or achieve remote code execution. Successful exploitation can lead to full site compromise. This vulnerability was remediated with commit c60bf04 (2025-06-16).

Weakness

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

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://gist.github.com/mcdruid/c0f7c42b28949c7d86cf77d0c674f398
• https://github.com/BeWelcome/rox
• https://github.com/BeWelcome/rox/commit/c60bf04
• https://www.vulncheck.com/advisories/rox-php-object-injection-rce
• https://gist.github.com/mcdruid/c0f7c42b28949c7d86cf77d0c674f398