2010 순천향대 정보보호 페스티벌 level9

Category : Coding , Reverse engineering

* binary

Summary : generate serial

[pwn3r@localhost ~]$ nc 192.168.0.13 8888 ZsIdTLcuTNYdJXa pwn3r Invalid router. Routing failed :( [pwn3r@localhost ~]$ nc 192.168.0.13 8888 ZxBSKUqrwwYqezO pwn3r Time out :(

[pwn3r@localhost ~]$ nc 192.168.0.13 8888 KOkIhGSyESyOWfW aaaaaaaaaaaaaaa WAN ssl Your key is wrong :(

exploit.py

#!/usr/bin/python from socket import * HOST = "127.0.0.1" PORT = 7799 s1 = "" s2 = "" org_key = "passwdplzidkwim" s = socket(AF_INET , SOCK_STREAM) s.connect((HOST , PORT)) print "[*] Connected !" s1 = s.recv(1024) print "[+] Receive : " + s1 for i in range(0 , len(org_key)):  if s1[i] <= "Z":   s2 += chr(ord(org_key[i])-0x20)  else:   s2 += org_key[i] evil = "" for i in range(0 , len(s2)):     if s1[i] < s2[i]:         evil += chr(ord(s2[i]) - ord(s1[i]) + ord('A'))     else:         evil += chr(ord(s1[i]) - ord(s2[i]) + ord('a')) print "[+] My serial : " + evil evil += " WAN ssl" s.send(evil + "\n") print "[+] Flag : " + s.recv(1024) s.close()

[pwn3r@localhost ~]$ ./exploit.py [*] Connected ! [+] Receive : pBEcUuutVZdYsCz [+] My serial : abOQCrfiEraoEGn [+] Flag : MerrySoloChristmas:)

Flag : MerrySoloChristmas:)