๋ณธ๋ฌธ ๋ฐ”๋กœ๊ฐ€๊ธฐ

โœ’๏ธ Reverse Engineering/Dreamhack3

[Dreamhack] rev-basic-2 WriteUp ๐Ÿœ rev-basic-2 WriteUp 1. ๋ฌธ์ œ ์„ค๋ช… ํ™•์ธ ํŒŒ์ผ ๋‹ค์šด๋กœ๋“œ 2. ๋‹ค์šด๋ฐ›์€ ์‘์šฉ ํ”„๋กœ๊ทธ๋žจ ์‹คํ–‰ ํ›„ ์ž„์˜์˜ ๋ฌธ์ž์—ด ์ž…๋ ฅ --> Enter ์„ ํด๋ฆญํ•˜๋‹ˆ ํ”„๋กœ๊ทธ๋žจ์ด ์ข…๋ฃŒ๋จ์„ ํ™•์ธ 3. x64dbg๋ฅผ ํ†ตํ•ด ์‘์šฉ ํ”„๋กœ๊ทธ๋žจ ์˜คํ”ˆ 4. ์ƒ๋‹จ์˜ '๊ธฐํ˜ธ' ํƒญ์—์„œ 'chall2.exe' ํด๋ฆญ 5. ์œ„์—์„œ๋ถ€ํ„ฐ ํƒ์ƒ‰ --> ๋ฌธ์ž์—ด์„ RCX ๋ ˆ์ง€์Šคํ„ฐ์— ์ž…๋ ฅ๋œ ๊ฐ’๊ณผ ๋ฐ˜๋ณต์ ์œผ๋กœ ๋น„๊ตํ•˜๋Š” ๊ตฌ๊ฐ„ ๋ฐœ๊ฒฌ 6. Hex dump ์—์„œ ๋น„๊ต๋˜๋Š” 7FF7B8F73000 ์ฃผ์†Œ ๊ฐ’ ํ™•์ธ --> ์ •๋‹ต ๋ฌธ์ž์—ด ๋ฐœ๊ฒฌ # ์•Œ์•„๋‚ธ FLAG : DH{Comp4re_the_arr4y} 7. ์•Œ์•„๋‚ธ FLAG ๊ฐ’ ์ž…๋ ฅ --> ๋ฌธ์ œ ํ•ด๊ฒฐ ์„ฑ๊ณต 2023. 11. 22.
[Dreamhack] rev-basic-1 WriteUp โ˜‚๏ธ rev-basic-1 WriteUp 1. ๋ฌธ์ œ ์„ค๋ช… ํ™•์ธ ํ›„ ํŒŒ์ผ ๋‹ค์šด๋กœ๋“œ 2. ๋‹ค์šด๋ฐ›์€ ์‘์šฉ ํ”„๋กœ๊ทธ๋žจ ์‹คํ–‰ ํ›„ ์ž„์˜์˜ ๋ฌธ์ž์—ด ์ž…๋ ฅ --> Enter ์„ ํด๋ฆญํ•˜๋‹ˆ ํ”„๋กœ๊ทธ๋žจ์ด ์ข…๋ฃŒ๋จ์„ ํ™•์ธ 3. x64dbg๋ฅผ ํ†ตํ•ด ์‘์šฉ ํ”„๋กœ๊ทธ๋žจ ์˜คํ”ˆ 4. ์ƒ๋‹จ์˜ '๊ธฐํ˜ธ' ํƒญ์—์„œ 'chall1.exe' ํด๋ฆญ 5. ์ž…๋ ฅ๋ฐ›์€ ๋ฌธ์ž์—ด์„ ์ •๋‹ต๊ณผ ๋น„๊ตํ•˜๋Š” ๋ถ€๋ถ„ ๋ฐœ๊ฒฌ --> ์ •๋‹ต์€ "DH{Compar3_the_ch4ract3r}" 6. ๋ฐœ๊ฒฌํ•œ FLAG ์ž…๋ ฅ --> ๋ฌธ์ œ ํ•ด๊ฒฐ ์„ฑ๊ณต 2023. 11. 20.
[Dreamhack] rev-basic-0 WriteUp ๐Ÿ™ rev-basic-0 WriteUp 1. ๋ฌธ์ œ ์„ค๋ช… ํ™•์ธ ํ›„ ํŒŒ์ผ ๋‹ค์šด๋กœ๋“œ 2. ๋‹ค์šด๋ฐ›์€ ์‘์šฉ ํ”„๋กœ๊ทธ๋žจ ์‹คํ–‰ ํ›„ ์ž„์˜์˜ ๋ฌธ์ž์—ด ์ž…๋ ฅ --> Enter ์„ ํด๋ฆญํ•˜๋‹ˆ ํ”„๋กœ๊ทธ๋žจ์ด ์ข…๋ฃŒ๋จ์„ ํ™•์ธ 3. IDA ๋ฅผ ํ†ตํ•ด ์‘์šฉ ํ”„๋กœ๊ทธ๋žจ ์˜คํ”ˆ 4. ๋ฌธ์ž์—ด ๊ฒ€์ƒ‰ ๊ธฐ๋Šฅ์„ ํ†ตํ•ด 'Correct' ๋ฉ”์‹œ์ง€ ๊ฒ€์ƒ‰ --> Wrong & Correct ๋ฉ”์‹œ์ง€ ๋ฐœ๊ฒฌ 5. ์œ„๋กœ ์Šคํฌ๋กคํ•˜๋‹ˆ ์ž…๋ ฅ๋ฐ›์€ ๋ฌธ์ž์—ด์„ ์ •๋‹ต๊ณผ ๋น„๊ตํ•˜๋Š” ๋ถ€๋ถ„ ๋ฐœ๊ฒฌ --> ์ •๋‹ต์€ "Compar3_the_str1ng" 6. ๋ฐœ๊ฒฌํ•œ FLAG ์ž…๋ ฅ --> ๋ฌธ์ œ ํ•ด๊ฒฐ ์„ฑ๊ณต 2023. 11. 19.