$ 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
antistatic
#anti-debugging#crackme
 Union 2021 24.34 files wu 1
Anti
#anti-debugging
 ICHSA 2021 – files wu 1
zzz
#angr-symbolic-execution
 n00bzCTF 2023 15.12 files wu 1
Boring_APK
#android-native-reversing#meet-in-the-middle (mitm)
 BKISC 2026 – files wu 1
Breaking_The_Vault_Uncover_the_Secrets
#android-native-reversing#ghidra
 BSidesTLV 2023 35.00 files wu 1
rolling
#android-native-reversing
 LINE 2022 – files wu 1
fire_in_the_androiddd
#android#jni-native#broadcast-receiver-intent
 darkCON 2021 24.06 files wu 1
watercolor
#android#jni#native-library#jadx
 S4CTF 2021 24.52 files wu 1
Memedrive
#android#jadx#xor#base64
 RITSEC 2021 – files wu 1
threelittlekeys
#android#apk-reversing#seeded-prng
 CyberSecurityRumble 2022 62.00 files wu 1
Lightbulb
#android#apk-reversing#rc4#java
 CyberSecurityRumble 2023 Quals 24.80 files wu 1
Free_Delivery
#android#apk-reversing#jadx
 UMassCTF 2024 43.10 files wu 1
3T-PHON3-HOM3
#android
 HackPack 2022 35.11 files wu 1
vault-door-3
#anagram#javascript-reversing
 picoCTF 2019 – files wu 1
Decompile
#algorithm-reimplementation
 OFPPT 2022 – files wu 1
Pascal
#algorithm-reimplementation
 OFPPT 2022 – files wu 1
I_HATE_THIS_APP_REVENGE
#aes-ctr-fixed-key
 LYKNCTF 2026 – files wu 1
Mystery
#aes-ctr
 Bhackari 2026 – files wu 1
rusty_vault
#aes
 DownUnderCTF 2024 68.04 files wu 1
baby_rev
#additive-cipher
 IrisCTF 2023 24.59 files wu 1
Impossible_Mission
#6502-assembly#c64-emulation-reversing
 1337UP 2023 24.23 files wu 1
atareee
#6502
 Hack.lu 2021 94.48 files wu 1
GODMODE_999 UIUCTF 2026 – files wu 1
Veil_of_Evernight UIUCTF 2026 – files wu 1
Vision VolgaCTF 2026 Quals 38.67 files wu 1
glyphs UIUCTF 2026 – files wu 1
nuclear_codes UMDCTF 2026 – files wu 1
vector_cache UIUCTF 2026 – files wu 1
Pluto_Chat SunshineCTF 2025 51.65 files wu 1
math_solver VuwCTF 2025 – files wu 1
nine_solves LA 2025 – files wu 1
Beginner_Rev SwampCTF 2024 40.40 files wu 1
Love_Debug UofTCTF 2024 23.90 files wu 1
Primitive_Reversing_2 UMassCTF 2024 43.10 files wu 1
Serpents_Pass BroncoCTF 2024 22.51 files wu 1
Summarize UIUCTF 2024 – files wu 1
Azusawa_s_Gacha_World SekaiCTF 2023 24.86 files wu 1
MCV5U BxMCTF 2023 – files wu 1
Solid_Reverse Cryptoverse 2023 24.52 files wu 1
absolute-cap TAMUctf 2023 – files wu 1