openxc/isotp-c thru commit 5a5d19245f65189202719321facd49ce6f5d46ac (2021-08-09) contains an out-of-bounds read in the ISO-TP Single Frame receive handler, where the 4-bit payload length nibble is used directly as the memcpy size without validating it against the actual CAN data length. A malicious CAN frame with an oversized length nibble can cause memory reads beyond the buffer, allowing attackers to cause a denial of service, or gain sensitive information.