SASCTF 2025 - blindspot (crypto) write-up

client.py더보기더보기더보기import astimport hashlibimport jsonimport queueimport secretsimport socketimport threadingimport timefrom ecdsa.curves import NIST256pfrom ecdsa.ellipticcurve import Point, PointJacobicurve = NIST256pgen = curve.generatorp = gen.order()def point2bytes(P): return P.to_bytes()def hash_func(Rp, m): if isinstance(m, str): m = m.encode() return ( int.from_byte..

• format_list_bulleted CTF
• · 2025. 5. 26.
• textsms

SASCTF 2025 - bigbabycode (crypto) write-up

task.py더보기더보기import numpy as npimport itertoolsR = 6N = 2**R - 1K = N - Rdef string_to_bits(s): bits = [] for ch in s: bits.extend(int(b) for b in format(ord(ch), '08b')) return bitsdef pad_and_split(bits, k): bb = bits.copy() bb.append(1) pad_len = (-len(bb)) % k bb.extend([0] * pad_len) return [bb[i:i+k] for i in range(0, len(bb), k)]def p2(x): return x != 0 a..

• format_list_bulleted CTF
• · 2025. 5. 26.
• textsms

[Network Forensic] MISC 풀어보기

심심해서 푼 문제들 정리 간단하게 했습니다.https://github.com/ctf-wiki/ctf-challenges/tree/master/misc/cap ctf-challenges/misc/cap at master · ctf-wiki/ctf-challengesContribute to ctf-wiki/ctf-challenges development by creating an account on GitHub.github.com  1. Google CTF 2016 a cute tegosaurus 귀여운 공룡이 나오는데 스테가노 기법이나 숨겨진 메시지는 없었다. 그냥 tcp의 urgent pointer에 플래그가 기록되어있다. tcp.urgent_pointer != 0 으로 긁어주면 한 바이트씩 플래그 유출..

• format_list_bulleted CTF
• · 2024. 5. 20.
• textsms