CTFlearn: Reykjavik


Determine the file type

Use the file command to determine the file type

Test the program


Use strings to print the sequences of printable characters in files


Dissemble the program

Using Ghidra we can see that the program utilizes the strcmp function with a userinput and flag.

Use GDB-Peda to analyze the program

Enter start to set a breakpoint at the main function.

Dissemble the main function and find the strcmp function.

Set the 2nd breakpoint at the strcmp function and run gdb.

The flag is stored in the RDI register.

Test the program

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