June 2013 archive

Defcon CTF Quals 2013 – \xff\xe4\xcc 4 (penser)

good luck. penser.shallweplayaga.me:8273 http://assets-2013.legitbs.net/liabilities/penser Download penser binary » Summary: x86_64 Unicode-proof shellcoding.

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Defcon CTF Quals 2013 – \xff\xe4\xcc 3 (linked)

typedef struct _llist { struct _llist *next; uint32_t tag; char data[100]; llist; and: register char *answer; char *(*func)(); llist *head; … func = (char *(*)(llist *))userBuf; answer = (char *)(*func)(head); send_string(answer); exit(0); Write me shellcode that traverses the randomly generated linked list, looking for a node with a tag 0x41414100, and returns a pointer to …

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Defcon CTF Quals 2013 – All Web Challenges (3dub)

Summary: 3dub (1) – babysfirst: SQLite SQL injection 3dub (2) – badmedicine: Stream cipher bit flipping 3dub (3) – hypeman: Rack/Sinatra session secret disclosure 3dub (4) – rememberme: Bruteforce 3dub (5) – worsemedicine: Block cipher bit flipping

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PHD CTF 2013 Hackskell (500)

We’ve got a screenshot of some encryption, here’s the text transcribed. Please say what’s there. Summary: a couple of modular equations

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PHD CTF 2013 from hell import crypto (100)

Decrypt the message: 7y9rr177sluqv1r4pw Hint: $ at

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PHD CTF 2013 ReStART (400)

We heard hellman encrypted the flag using his super secure keygen. Break it! Summary: RSA with the lower half of the secret exponent bits leaked.

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