CTF challenges & writeups

134 challenges in family ⊕ crypto:classical ✕ clear · browse all techniques

Challenge	CTF	Weight	Category	Has
child-re #xor #static-analysis	WolvCTF 2023	24.33	Reverse	files wu 1
cbc #classical-cipher #cbc-mode	corCTF 2023	36.97	Crypto	files wu 1
x0rr3al #xor #string-obfuscation	vsCTF 2023	23.32	Reverse	files wu 1
FunFact #single-byte-xor	BYUCTF 2022	–	Reverse	files src wu 1
XQR #xor #qr-code	BYUCTF 2022	–	Crypto	files src wu 2
desrever #rot13	ImaginaryCTF 2022	24.65	Reverse	files wu 1
Secure_Notes #otp-bruteforce	NahamCon 2022	24.61	Mobile	files wu 2
XORROX #xor-keystream-reversal	NahamCon 2022	24.61	Crypto	files wu 3
XOR #known-plaintext-xor	OFPPT 2022	–	Crypto	files wu 2
Barry #bigram-substitution #cryptogram	PatriotCTF 2022	24.52	Crypto	files src wu 1
Cowsay #repeating-key-xor #xortool	PatriotCTF 2022	24.52	Crypto	files src wu 1
TallestHeader #file-signature-repair #transposition-cipher #binwalk	VishwaCTF 2022	20.79	Crypto	files wu 1
turbocrab #jit-shellcode #substitution-recovery	corCTF 2022	24.92	Reverse	files src wu 1
Digitally_Encrypted_1 #logic-circuit-reversing #xor-cipher	BCACTF 2021	–	Reverse	files wu 2
Digitally_Encrypted_2.99999 #logic-circuit-reversing #shift-xor-cipher-inversion	BCACTF 2021	–	Reverse	files wu 1
Digitally_Encrypted_3 #logic-circuit-reversing #shift-add-xor-cipher	BCACTF 2021	–	Reverse	files wu 1
Sailing_Thru_Decryption #signal-flag-decoding #binary #vigenere-cipher	BCACTF 2021	–	Crypto	files wu 2
Storytime_The_Tragic_Interlude #xor-decryption	BCACTF 2021	–	Reverse	files wu 2
OTP1 #repeating-key-xor #xortool	BlueHens 2021	22.62	Crypto	files wu 1
OTP2 #xor #known-plaintext	BlueHens 2021	22.62	Crypto	files wu 1
A_Different_Type_of_Serial_Key #hardware #logic-analyzer #spi #i2c #xor-decode	CSAW 2021 Quals	20.54	Hardware	files wu 1
RoccaPia #reversing #xor-cipher	DaVinciCTF 2021	24.50	Reverse	files wu 3
Substitution #substitution-cipher #atbash	DaVinciCTF 2021	24.50	Crypto	files wu 3
xorpals #single-byte-xor #bruteforce	DamCTF 2021	24.43	Crypto	files wu 3
Back_to_the_Lab_1 #reversing #xor #per-substring-check	DawgCTF 2021	23.29	Reverse	files wu 1
Cooking_the_Books #classical-cipher #rot47 #cyberchef #multi-encoding	DawgCTF 2021	23.29	Crypto	files wu 1
Who_am_I #reversing #byte-assembly #xor	DawgCTF 2021	23.29	Reverse	files wu 1
Code_Decode #substitution-cipher #embedded-key	DeconstruCT.F 2021	19.69	Crypto	files wu 3
Substitution_Cipher_I #substitution-cipher	DownUnderCTF 2021	–	Crypto	files src wu 3
aptenodytes-forsteri #substitution-cipher	HSCTF 2021	–	Crypto	files src wu 2
queen-of-the-hill #hill-cipher	HSCTF 2021	–	Crypto	files src wu 2
CaesarMirror #rot13	HacktivityCon 2021	–	Crypto	files wu 3
Perfect_XOR #xor	HacktivityCon 2021	–	Crypto	files wu 3
h4XOR #repeating-key-xor	HeroCTF 2021	35.17	Crypto	files wu 3
Jumprope #xor-keystream	ImaginaryCTF 2021	–	Reverse	files wu 2
Stings #substitution-cipher	ImaginaryCTF 2021	–	Reverse	files wu 3
A_to_Z #atbash-cipher	MetaCTF 2021	–	Crypto	files wu 3
Getting_Darryl_Back #xor-decryption-reversing	MetaCTF 2021	–	Reverse	files wu 1
Unbreakable_Encryption #otp-key-reuse	MetaCTF 2021	–	Crypto	files wu 2
Memedrive #android #jadx #xor #base64	RITSEC 2021	–	Reverse	files wu 1

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