Vulnerability Advisory : CVE-2026-42485 with LOW Attack Complexity

AGL agl-service-can-low-level contains a stack buffer overflow in the uds-c library. The send_diagnostic_request function in uds.c allocates a 6-byte stack buffer (MAX_DIAGNOSTIC_PAYLOAD_SIZE=6) but copies up to 7 bytes (MAX_UDS_REQUEST_PAYLOAD_LENGTH=7) via memcpy at an offset of 1+pid_length (2-3 bytes), resulting in 1-4 bytes of controlled stack overflow. The payload_length field (uint8_t) has no bounds check against the destination buffer. On 32-bit ARM automotive ECUs without stack canaries, this can lead to return address overwrite and RCE.