CVE-2026-43894 jq: Wild stack write via signed-integer overflow in decNumber D2U() macro

jq is a command-line JSON processor. In 1.8.1 and earlier, when decNumberFromString is given a number literal of INTMAX-1 2147483646 digits, the D2U macro overflows during signed-int arithmetic. The wrapped negative value bypasses the heap-allocation size check, causes the function to use a 30-by...