Writeup in progress
Currently making the solution for tic-tacand the walkthrough will be published here as soon as it's ready.
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tic-tac
Published: April 26, 2023
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Useful tools for Binary Exploitation
- Hex ViewerView text or raw hex bytes as a xxd-style hex dump with byte offset, hex columns, and ASCII sidebar. Highlights printable characters and null bytes.
- Binary CalculatorPerform binary arithmetic (add, subtract, multiply, divide) with copyable outputs in every base.
- Bit Shift CalculatorPerform left/right bit shifts and see the result across binary, octal, decimal, and hex.
- Number Base ConverterConvert numbers between binary, octal, decimal, and hexadecimal instantly. Enter any value and see all four bases update in real time.
Related reading
- Format String Vulnerabilities for CTF Binary ExploitationA beginner-friendly guide to format string vulnerabilities in CTF binary exploitation: how printf leaks memory, finding the format string offset, writing arbitrary values with %n, and walking through the picoCTF format string series.
- Using GDB for CTF Reverse EngineeringA practical guide to GDB for CTF competitions: running binaries, setting breakpoints, reading registers, inspecting memory, and tracing through the Bit-O-Asm and GDB baby step challenge series.
What to try next
- Binary ExploitationHard
Heap Havoc
Overflow the input buffer to overwrite the saved return address and redirect execution to the flag-printing function.
- Binary ExploitationHard
offset-cycleV2
Timed ret2win buffer overflow where each instance uses a different offset. Automate the cyclic-pattern detection and exploit with pwntools to beat the clock.
- Binary ExploitationHard
Pizza Router
Plan the fastest pizza drone routes and snag a slice of the flag. Exploit out-of-bounds heap access in a grid routing binary.
- Binary ExploitationHard
handoff
A shellcode handoff challenge with strict input constraints. Craft a minimal payload that passes control to shellcode and reads the flag.
- Binary ExploitationHard
babygame03
A harder babygame with new map mechanics. Abuse out-of-bounds movement to manipulate game state and trigger flag output.