> For the complete documentation index, see [llms.txt](https://docs.cooku222.kr/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.cooku222.kr/security/mobile/owasp-mas-crackme/android-uncrackable-level3.md).

# Android UnCrackable Level3

문제 파일 : <https://mas.owasp.org/crackmes/Android/>

***

<figure><img src="https://blog.kakaocdn.net/dna/bfPlKQ/dJMcagYbRYG/AAAAAAAAAAAAAAAAAAAAAJKapzbGwSWo8xrPXvCCef41RS6Gl-P1jNGFWvw7ITJT/img.png?credential=yqXZFxpELC7KVnFOS48ylbz2pIh7yKj8&#x26;expires=1782831599&#x26;allow_ip=&#x26;allow_referer=&#x26;signature=2mQfzVjXeONORq7MIy%2FGGeM%2FTEo%3D" alt="" height="246" width="697"><figcaption></figcaption></figure>

평문 pizzapizzapizzapizzapizz에 XOR 난독화를 진행해주는 것으로 보인다.

<figure><img src="https://blog.kakaocdn.net/dna/lAzWq/dJMcaaDFzTe/AAAAAAAAAAAAAAAAAAAAAF72Rlk6CWAj-xRJxhYgb9o2oqAycykhcqSXxRizmxt-/img.png?credential=yqXZFxpELC7KVnFOS48ylbz2pIh7yKj8&#x26;expires=1782831599&#x26;allow_ip=&#x26;allow_referer=&#x26;signature=Aj2sqSIxHURdlM2ibYAkacvQIRc%3D" alt="" height="382" width="1082"><figcaption></figcaption></figure>

마찬가지로 check\_code에서 판별되고 있다.&#x20;

<figure><img src="https://blog.kakaocdn.net/dna/bQBLsa/dJMcaawT6kM/AAAAAAAAAAAAAAAAAAAAAH1LvcL0g0ZcU4RXOOC9veiG7w_WRey9DO8U4eYwWoEZ/img.png?credential=yqXZFxpELC7KVnFOS48ylbz2pIh7yKj8&#x26;expires=1782831599&#x26;allow_ip=&#x26;allow_referer=&#x26;signature=zorLDw4PTUn2R68JgO2sw0JDtuU%3D" alt="" height="316" width="667"><figcaption></figcaption></figure>

마찬가지로 bar() 함수의 로직을 찾아 XOR input 값을 받아 어떤 문자열을 받는지 확인한다.\
&#x20;\
FLAG : making owasp great again&#x20;

<figure><img src="https://blog.kakaocdn.net/dna/9XOU1/dJMcafZhBSZ/AAAAAAAAAAAAAAAAAAAAABrH6A3-bmj2niAhWfCiCEORKMvacQMtluGAY_BZ_wym/img.png?credential=yqXZFxpELC7KVnFOS48ylbz2pIh7yKj8&#x26;expires=1782831599&#x26;allow_ip=&#x26;allow_referer=&#x26;signature=ss6Jc%2B%2FZXjS3LIqGt7olhJVV024%3D" alt="" height="843" width="1597"><figcaption></figcaption></figure>

<br>


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