Improper Restriction of Operations within the Bounds of a Memory Buffer
An issue was discovered on Vera VeraEdge 1.7.19 and Veralite 1.7.481 devices. The device provides UPnP services that are available on port 3480 and can also be accessed via port 80 using the url "/port_3480". It seems that the UPnP services provide "request_image" as one of the service actions for a normal user to retrieve an image from a camera that is controlled by the controller. It seems that the "URL" parameter passed in the query string is not sanitized and is stored on the stack which allows an attacker to overflow the buffer. The function "LU::Generic_IP_Camera_Manager::REQ_Image" is activated when the lu_request_image is passed as the "id" parameter in query string. This function then calls "LU::Generic_IP_Camera_Manager::GetUrlFromArguments" and passes a "pointer" to the function where it will be allowed to store the value from the URL parameter. This pointer is passed as the second parameter $a2 to the function "LU::Generic_IP_Camera_Manager::GetUrlFromArguments". However, neither the callee or the caller in this case performs a simple length check and as a result an attacker who is able to send more than 1336 characters can easily overflow the values stored on the stack including the $RA value and thus execute code on the device.
CWE-119 - Buffer Overflow
Buffer overflow attacks involve data transit and operations exceeding the restricted memory buffer, thereby corrupting or overwriting data in adjacent memory locations. Such overflow allows the attacker to run arbitrary code or manipulate the existing code to cause privilege escalation, data breach, denial of service, system crash and even complete system compromise. Given that languages such as C and C++ lack default safeguards against overwriting or accessing data in their memory, applications utilizing these languages are most susceptible to buffer overflows attacks.