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Challenges

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38 challenges in family ⊕ crypto:key-recovery ✕ clear · browse all techniques

Challenge CTF Weight Category Has
BabyLCG
#lcg-state-recovery
 L3akCTF 2026 34.47 Crypto files wu 1
RepusPing
#ptr-guard-key-recovery
 MntcrlCTF 2026 25.00 Pwn files wu 1
mafuyuuuuu
#xoshiro256#prng-state-recovery#dotnet-random
 R3CTF 2026 35.95 Misc files wu 1
rps_casino
#lfsr#gf2-linear-system#z3#state-recovery
 DiceCTF 2024 Quals 54.40 Crypto files wu 2
yaonet
#ecdsa#partial-key-exposure#bsgs#discrete-log#nist-p256
 DiceCTF 2024 Quals 54.40 Crypto files wu 1
leaving_soon
#drm-key-recovery
 justCTF 2024 Quals 77.17 Misc files wu 3
Really_Secure_Apparently
#rsa#wiener-attack#small-private-exponent
 1337UP 2023 24.23 Crypto files wu 2
Insights
#rsa#predictable-private-exponent
 Crypto 2023 59.60 Misc files wu 1
Fractional_Flag
#rsa-variant#wiener-lattice-attack#small-private-exponent
 Cryptoverse 2023 24.52 Crypto files wu 1
bivalves
#z3#state-recovery
 PlaidCTF 2023 100.00 Crypto files wu 2
Complicated_Function
#rsa#partial-key-exposure#coppersmith
 TSG 2023 – Crypto files wu 3
CwyptographicOwacle
#ecdsa#signature-oracle#private-key-recovery#aes
 DaVinciCTF 2022 24.50 Crypto files wu 1
small_weiner
#rsa#boneh-durfee#lattice#small-private-exponent
 DaVinciCTF 2022 24.50 Crypto files wu 2
learning-without-errors
#rlwe#ckks#lattice#key-recovery
 DiceCTF 2022 24.82 Crypto files wu 1
CorruptAAAAd
#rsa#corrupted-private-key#public-exponent-bruteforce
 PatriotCTF 2022 24.52 Crypto files wu 2
RSAGoneWrong
#rsa#phi-factorization#prime-combination
 RITSEC 2022 – Crypto files wu 1
Bro-key-n
#rsa#partial-key-recovery
 UIUCTF 2022 – Crypto files wu 1
DamaS
#rsa#boneh-durfee#small-private-exponent#coppersmith
 ASIS 2021 Quals 89.22 Crypto files wu 1
Triplet
#rsa#shared-exponent-multiple-moduli#phi-multiple
 Crypto 2021 36.00 Misc files wu 2
frozen
#signature-forgery#masked-key-recovery#modular-inverse
 Crypto 2021 36.00 Misc files wu 1
keybase
#aes-cbc#partial-key-bruteforce#iv-recovery
 Crypto 2021 36.00 Misc files wu 2
regulus-satrapa
#partial-key-exposure
 HSCTF 2021 – Crypto files wu 1
real_mersenne
#mt19937#state-recovery#float-prediction
 Zh3r0 2021 – Crypto files src wu 2
twist_and_shout
#mt19937#state-recovery#untwist
 Zh3r0 2021 – Crypto files src wu 2
sidhe
#sidh#adaptive-key-recovery#static-key-reuse
 PlaidCTF 2020 93.15 Crypto files wu 3
forgetful
#rsa#phi-multiple-leak#factoring
 plfanzen 2026 25.00 Crypto files wu 1
The_Phantom_Menace
#private-key-disclosure
 LakeCTF 2025 Quals – Crypto files wu 1
DIY_enc
#aes-ctr#base64-padding-position#key-recovery
 DanteCTF 2023 24.44 Crypto files wu 1
Big_RSA
#rsa#phi-leak-factorization
 TeamItaly 2023 24.88 Crypto files wu 1
PrimeGuesser1
#rlwe-key-recovery
 KITCTFCTF 2022 – Crypto files wu 2
PrimeGuesser2
#rlwe-key-recovery
 KITCTFCTF 2022 – Crypto files wu 2
eazy-RSA
#rsa#e-and-phi-not-coprime#modular-square-root#crt
 0x41414141 2021 – Crypto files wu 3
Damn_Randomware
#rsa#leaked-private-key
 BSidesTLV 2021 23.94 Crypto files wu 1
A_Simple_SP_Box
#substitution-permutation-network#block-cipher#chosen-plaintext#key-recovery
 DCTF 2021 – Crypto files wu 2
Lockpicking
#lfsr#cows-and-bulls#state-recovery
 DCTF 2021 – Crypto files wu 1
Private_Encryption_Mistake
#rsa#partial-private-key-recovery#ocr
 DCTF 2021 – Crypto files wu 1
Cozzmic_Dizzcovery
#xor-state-recovery
 K3RN3LCTF 2021 24.37 Crypto files wu 1
mini-A3S
#affine-sbox#linear-cryptanalysis#gf3#key-recovery
 RaRCTF 2021 24.53 Crypto files wu 1