Flag Checker
Flag checkers are a common type of challenge in the Reverse Engineering category.
An executable or script called a flag checker takes the player's input and outputs whether that input matches the flag.
These challenges may also be called "crackmes" in a broader sense. (automatically translated from Japanese)
Flag Checker Challenges
Leaked Flag Checker
minaminao
Rev739 solvesRuby Flag Checker
hiikunz
Rev356 solvesread-a-binary
tan90909090
Rev294 solvesglibc's secret function
tan90909090
Rev262 solvesSugoi Flag Checker
chocorusk
Rev243 solvesmisdirection
tan90909090
Rev214 solvesmasking tape
arata-nvm
Rev191 solvesREADME.pdf
arata-nvm
Rev169 solvesMirage
serioton
Rev167 solvesOptimized expression
tan90909090
Rev153 solvesSimple Flag Checker
keymoon
Rev136 solvesC++ flag checker
tan90909090
Rev96 solvesC# File-based app
tan90909090
Rev93 solvesAlpacaForm
shiragi
Rev88 solvesBINARY IN THE FUTURE.
yu212
Rev75 solveshidden
arata-nvm
Rev75 solveswrong instruction
tan90909090
Rev65 solvesCompile time flag checker
tan90909090
Rev64 solvesdecompile me
ptr-yudai
Rev52 solvesRemnant
2501
Misc47 solvesx32 ABI flag checker
tan90909090
Rev39 solvesJerry's flag checker
soon-haari
Crypto37 solvesvcipher
sugi
Rev34 solvespytecode
xornet
Rev29 solvesmimikyu
ptr-yudai
Rev20 solvessubway
arata-nvm
Rev19 solvesI2C Device
ptr-yudai
Rev15 solvesJump
n01e0
Rev12 solvesfvm
ptr-yudai
Rev11 solvesimgchk
ptr-yudai
Rev11 solvestopology
ptr-yudai
Rev9 solvesChirashi-sushi
keymoon
Rev5 solvesJump-bugfix
n01e0
Rev5 solvesq-solved
ptr-yudai
QuantumRev4 solves