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๐ŸดCTF/DreamHack

DreamHack - funjs ํ’€์ด

by Janger 2023. 9. 9.
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๊ฐœ๋ฐœ์ž ๋„๊ตฌ์— Sources ํƒญ์—์„œ ๋ธŒ๋ ˆ์ดํฌ ํฌ์ธํŠธ๋ฅผ ๊ฑฐ๋Š” ๊ฒƒ์ด ํ•ต์‹ฌ

if (flag[_0x374fd6(0x17c)] != 0x24) {

์ฒ˜์Œ์— ์ด ์กฐ๊ฑด๋ฌธ ๋•Œ๋ฌธ์— ์ž๊พธ NOP! ๊ฐ€ ์ถœ๋ ฅ์ด ๋˜๋Š”๋ฐ ๋ฌด์Šจ ๋‚ด์šฉ์ธ์ง€ ํ™•์ธํ•˜๋ ค๋ฉด Console ์ฐฝ์—๋‹ค๊ฐ€ flag[_0x374fd6(0x17c)]์™€ 0x24๋ฅผ ๊ฐ๊ฐ ์ž…๋ ฅ ๊ทธ ๊ฒฐ๊ณผ if (flag.length != 36)๋ฅผ ๋œปํ•˜๋Š” ๊ฒƒ์„ ํ™•์ธ ํ”Œ๋ž˜๊ทธ ์ž…๋ ฅ ๊ฐ’์„ ์ผ๋ถ€๋กœ 36๊ธ€์ž๋กœ ์ž…๋ ฅํ•ด์„œ ๋‹ค์Œ ๋ผ์ธ์„ ์ง„ํ–‰ํ•˜์˜€๋‹ค. 

 

์œ„์™€ ๋น„์Šทํ•˜๊ฒŒ ํ•œ์ค„ํ•œ์ค„ ์ง„ํ–‰ ๊ณผ์ •์„ ํ™•์ธํ•˜๋ฉด์„œ ๋“œ๋””์–ด ์‚ฌ์šฉ์ž ์ž…๋ ฅ ๊ฐ’๊ณผ ์‹ค์ œ flag ๊ฐ’์„ ๋น„๊ตํ•˜๋Š” ๋ฐ˜๋ณต๋ฌธ์„ ์ฐพ์•„์ฃผ์—ˆ๋Š”๋ฐ ๋‚œ ์•„๋ž˜์ฒ˜๋Ÿผ ์ˆ˜์ •์„ ํ•˜์—ฌ ์ง„์งœ flag ๊ฐ’์„ ์ฐพ์„ ์ˆ˜ ์žˆ์—ˆ๋‹ค.

result = ""
for (var i = 0x0; i < flag[_0x374fd6(0x17c)]; i++) {
    result += String.fromCharCode(operator[i % operator[_0x374fd6(0x17c)]](_0x4949[i], _0x42931[i]));
}

console.log(result)
text2img(result);
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