A vulnerability was found in ZhongBangKeJi CRMEB up to 5.4.0 and classified as critical. Affected by this issue is the function get_image_base64 of the file PublicController.php. The manipulation of the argument file leads to deserialization. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. VDB-272066 is the identifier assigned to this vulnerability. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.
The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Crmeb | Zhongbangkeji | * | 5.4.0 (including) |
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.