$ ctf42

Reverse CTF challenges

4,044 Reverse CTF challenges from 397 CTFs (2011–2026), 511 with writeups.

Top reverse techniques

#reversing 77 #xor 24 #z3 15 #vm-reversing 13 #constraint-solving 10 #static-analysis 9 #strings 9 #android 9 #anti-debugging 7 #symbolic-execution 6 #dotnet-reversing 6 #xor-cipher 5 #angr 5 #windows-reversing 5 #binary-patching 5

Challenges

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Challenge CTF Weight Has
Function_Pointer_Fun
#z3
 HackPack 2021 24.31 files wu 3
x-and-or
#xor-decrypted-self-modifying-code#mmap
 0x41414141 2021 – files wu 3
Exhell
#xlsx
 HackPack 2021 24.31 files wu 3
LostInYourEyes
#vm-reversing#custom-bytecode#ida
 DiceCTF 2021 24.82 files wu 3
ncore
#verilog-softcore-reversing#custom-isa#bytecode-crafting#enclave-dump
 CSAW 2021 Quals 20.54 files wu 3
Normal
#verilog-reversing
 ImaginaryCTF 2021 – files wu 3
Stings
#substitution-cipher
 ImaginaryCTF 2021 – files wu 3
There_Are_No_Strings_on_Me
#strings-analysis
 MetaCTF 2021 – files wu 3
StringyThings
#strings
 UTCTF 2021 – files wu 3
aplet321
#string-count-bypass
 LA 2024 – files wu 3
EasyAssembly
#static-analysis
 HeroCTF 2021 35.17 files wu 3
Famous_Pin
#static-analysis
 eHaCON 2021 – files wu 3
Seeking_the_flag
#static-analysis
 eHaCON 2021 – files wu 3
reee
#self-unpacking#z3
 PlaidCTF 2020 93.15 files wu 3
hvhpgssynt
#rot13
 UIUCTF 2021 – files wu 3
RoccaPia
#reversing#xor-cipher
 DaVinciCTF 2021 24.50 files wu 3
vmwhere1
#reversing#vm
 UIUCTF 2023 – files wu 3
vmwhere2
#reversing#vm
 UIUCTF 2023 – files wu 3
Secret_App
#reversing#strings#hardcoded-credentials
 DawgCTF 2021 23.29 files wu 3
Scraps
#reversing#stack-strings#ida
 DeconstruCT.F 2021 19.69 files wu 3
CrackMe
#reversing#hash-byte-reversal#hashcat
 DaVinciCTF 2021 24.50 files wu 3
Just_In_Time
#reversing#dynamic-analysis#breakpoint-flag-extraction
 DCTF 2021 – files wu 3
checker
#reversing#bit-manipulation#inverse-transform
 CSAW 2021 Quals 20.54 files wu 3
Bell
#reversing#algorithm-replication#interactive
 DCTF 2021 – files wu 3
beginners_rev_2023
#reversing
 TSG 2023 – files wu 3
Run-ELF
#reversing
 UTCTF 2021 – files wu 3
The_Flag_Vault
#reversed-string
 KnightCTF 2022 17.38 files wu 3
multidimensional
#reverse-engineering
 HSCTF 2021 – files src wu 3
Recur
#recursion#memoization
 UTCTF 2021 – files wu 3
All_Worbled_Up
#python-bytecode-reversing#adler32
 UofTCTF 2024 23.90 files wu 3
sneks
#python-bytecode
 HSCTF 2021 – files wu 3
snek
#pyc-decompile#uncompyle6
 RITSEC 2021 – files wu 3
Dill
#pyc-decompilation
 SunshineCTF 2023 34.09 files wu 3
Scadomware
#predictable-key
 Intent 2021 19.97 files wu 3
Obfuscation
#obfuscated-c#byte-transform-reversing
 1337UP 2023 24.23 files wu 3
just_TV
#mheg-reversing
 justCTF 2024 Quals 77.17 files wu 3
Dummyper
#memory-dump-reversing#xor-self-encryption#known-plaintext-endbr64
 Aero 2021 35.17 files wu 3
parallel-the-m0le
#meet-in-the-middle (mitm)
 m0leCon 2021 Quals 24.55 files wu 3
infected
#ld-preload#function-hooking#backdoor
 zer0pts 2021 24.56 files wu 3
RUN
#keygen#reversing
 Securinets 2021 Quals 41.71 files wu 3