Root-Me/ELF64 - PID encryption·15ptsELF64 - PID encryption — Root-MeCrypto challenge ELF64 - PID encryption: classical cipher layers and modular arithmetic.Cryptomedium#crypto#root-me#mediumMay 26, 2026
Root-Me/File - PKZIP·15ptsFile - PKZIP — Root-MeCrypto challenge File - PKZIP: classical cipher layers and modular arithmetic.Cryptomedium#crypto#root-me#mediumMay 26, 2026
Root-Me/Pixel Madness·15ptsPixel Madness — Root-MeCrypto challenge Pixel Madness: classical cipher layers and modular arithmetic.Cryptomedium#crypto#root-me#mediumMay 26, 2026
Root-Me/Monoalphabetic substitution - Caesar·15ptsMonoalphabetic substitution - Caesar — Root-MeCrypto challenge Monoalphabetic substitution - Caesar: classical cipher layers and modular arithmetic.Cryptomedium#crypto#root-me#mediumMay 26, 2026
Root-Me/CISCO - Salted Password·10ptsCISCO - Salted Password — Root-MeFor CISCO - Salted Password, ciphertext structure suggests hybrid encoding.Cryptoeasy#crypto#root-me#easyMay 26, 2026
Root-Me/Shift cipher·10ptsShift cipher — Root-MeCrypto challenge Shift cipher: classical cipher layers and modular arithmetic.Cryptoeasy#crypto#root-me#easyMay 26, 2026
Root-Me/Hash - SHA-2·5ptsHash - SHA-2 — Root-MeCryptanalysis path for Hash - SHA-2 — algebraic manipulation, small subgroup checks, and a plausible attack narrative without dumping complete secret material..Cryptoeasy#crypto#root-me#easyMay 26, 2026
Root-Me/Hash - Message Digest 5·5ptsHash - Message Digest 5 — Root-MeCryptanalysis path for Hash - Message Digest 5 — algebraic manipulation, small subgroup checks, and a plausible attack narrative without dumping complete secret material..Cryptoeasy#crypto#root-me#easyMay 26, 2026
Root-Me/Encoding - ASCII·5ptsEncoding - ASCII — Root-MeCrypto challenge Encoding - ASCII: classical cipher layers and modular arithmetic.Cryptoeasy#crypto#root-me#easyMay 26, 2026
CryptoHack/RSA Starter 1·10ptsRSA Starter 1 — CryptoHackCompute 101^17 mod 22663 — the foundational primitive that powers every later RSA challenge.Cryptoeasy#crypto#rsa#modular-exponentiationMay 16, 2026
picoCTF/Mod 26·10ptsMod 26 — picoCTFROT-13 the ciphertext — the title is a hint.Cryptoeasy#beginner#crypto#caesarMay 16, 2026
picoCTF 2024/Weirder RSA·200ptsWeirder RSA — solving with lattice reductionSmall private exponent: Wiener attack via continued fractions recovers d directly.CryptomediumMedium#crypto#rsa#wienerMay 16, 2026
Hack The Box/Weak RSA·20ptsHTB Weak RSA — factoring small N with FactorDBPublic modulus is in FactorDB. Recover p,q,d in seconds and decrypt the ciphertext.Cryptoeasy#crypto#rsa#factordbMay 16, 2026
NCTF 2026/Crypto 101·100ptsCrypto 101 — NCTF 2026Beginner crypto — community writeups on CTFtime.CryptoeasyCTFtime#crypto#2026#nctf-2026Apr 5, 2026
HITCON CTF 2025/SignIn·400ptsSignIn — HITCON CTF 2025Cryptography challenge from HITCON 2025.CryptohardBlog#crypto#hitcon-ctf-2025#hitconAug 4, 2025
Google CTF 2025/crypto-backdoor·300ptscrypto-backdoor — Google CTF 2025Official Google CTF 2025 quals archive on GitHub.CryptohardGitHub#crypto#google-ctf-2025#google-ctfJun 29, 2025
DEF CON CTF 33 Quals/holographic·350ptsholographic — DEF CON CTF 33 QualsCryptography challenge from the 2025 qualifier archive.CryptohardGitHub#crypto#defcon-33-quals#defconMay 18, 2025
PlaidCTF 2025/Tales from the Crypt·500ptsTales from the Crypt — PlaidCTF 2025TLS renegotiation leaks partial RSA private key material — recover d via Coppersmith.CryptoinsaneBlog#crypto#rsa#plaidctf-2025Apr 6, 2025
picoCTF 2025/Quantum Scrambler·300ptsQuantum Scrambler — picoCTF 2025Harder crypto challenge from the 2025 scoreboard.CryptohardBlog#crypto#picoctf-2025#picoctfMar 17, 2025
picoCTF 2025/EVEN RSA CAN BE BROKEN???·200ptsEVEN RSA CAN BE BROKEN??? — picoCTF 2025RSA with an even public exponent — factor N and decrypt.CryptomediumBlog#crypto#rsa#picoctf-2025Mar 17, 2025