CVE-2026-37532: AGL agl-service-can-low-level thru 17

AGL agl-service-can-low-level thru 17.1.12 contains a heap buffer over-read in the isotp-c library. In isotp_continue_receive (receive.c:87-89), the payload_length for a Single Frame is extracted from a 4-bit nibble in the CAN frame data, yielding values 0-15. However, a standard CAN frame is only 8 bytes, with payload starting at data[1] (7 bytes available). When payload_length exceeds the available data (e.g., nibble=15 but only 7 payload bytes exist), memcpy(message.payload, &data[1], payload_length) reads up to 8 bytes past the end of the data buffer.