解flag

bash -lc python3 - <<'PY' import hashlib,hmac,itertools,string,math ct=bytes.fromhex('6bcc444558c4248b64763a1d61bea7803257e13cedccc06d9042ad8ff96190392b54d09752c6') seq=0x7c3a0c7a; seq0=0x7c3a0c79; ack=0x7814bd4b starts=set([seq,seq0,ack,seq+5,seq+81,seq+86,seq-5,seq>>7,seq0>>7,ack>>7,seq & 0xffff,seq>>16,seq0 & 0xffff,0x7f3a,0x7c3a,0xc79,0xc7a,0x2000,0x2000<<7,50432-49152,50432,443,3,7]) seeds=[] for A in ['2026-01-18T22:54:12Z','2026-01-19T22:54:12Z','2026-01-18 22:54:12','1768776852']: for B in ['2026-01-18T22:27:33Z','2026-01-18T23:27:33Z','2026-01-19T00:27:33Z','1768775253']: for C in ['2026-01-18T22:56:21Z','2026-01-19T22:56:21Z','1768776981']: for pre in ['','KEYMAT:']: seeds.append(f'{pre}AURORA-ER|flight=LX-517|syn={A}|idl={B}|a2={C}'.encode())

def stream(seed,kind,st): key=hashlib.sha256(seed).digest();out=b'';i=st while len(out)<len(ct): if kind=='key4': block=hashlib.sha256(key+i.to_bytes(4,'big')).digest() elif kind=='key4le': block=hashlib.sha256(key+i.to_bytes(4,'little')).digest() elif kind=='key8': block=hashlib.sha256(key+i.to_bytes(8,'big')).digest() elif kind=='seed4': block=hashlib.sha256(seed+i.to_bytes(4,'big')).digest() elif kind=='seed8': block=hashlib.sha256(seed+i.to_bytes(8,'big')).digest() elif kind=='seeddec': block=hashlib.sha256(seed+str(i).encode()).digest() elif kind=='seedpipe': block=hashlib.sha256(seed+b'|'+str(i).encode()).digest() out += block; i += 1 return out[:len(ct)] for seed in seeds: for kind in ['key4','key4le','key8','seed4','seed8','seeddec','seedpipe']: for st in starts: try: ks=stream(seed,kind,st) except Exception: continue pt=bytes(a^b for a,b in zip(ct,ks)) if b'flag' in pt.lower() or sum(32<=c<127 for c in pt)>34: print('hit',kind,st,hex(st),repr(pt),seed); raise SystemExit print('no') PY

Thought for 26m 19s