Hasher 1

spbctf

Task: Linux x86-64 PIE crackme (hasher1.elf) validating a 41-char serial through two gates — an MD5 check on 6 specific chars plus an obfuscated xor state machine. Solution: extract the hardcoded MD5 target, brute-force its 6-char preimage with hashcat, then solve the flattened check_serial with angr using those chars as fixed constraints (rebasing PIE addresses to base 0x400000).