Ashlar-Vellum Cobalt XE File Parsing Untrusted Pointer Dereference Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Ashlar-Vellum Cobalt. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.
The specific flaw exists within the parsing of XE files. The issue results from the lack of proper validation of a user-supplied value prior to dereferencing it as a pointer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-17948.
The product obtains a value from an untrusted source, converts this value to a pointer, and dereferences the resulting pointer.
An attacker can supply a pointer for memory locations that the product is not expecting. If the pointer is dereferenced for a write operation, the attack might allow modification of critical state variables, cause a crash, or execute code. If the dereferencing operation is for a read, then the attack might allow reading of sensitive data, cause a crash, or set a variable to an unexpected value (since the value will be read from an unexpected memory location). There are several variants of this weakness, including but not necessarily limited to: