[unix-pc.general] Security problem on UNIX PC's

lenny@quincy.UUCP (09/23/87)

Security problem #1:

Under release 3.5 or more.  Send mail to yourself on 3B1, wait for the
<MAIL ENVELOPE> icon and then press either <MSG> or point to it with mouse and
press <B1>.  You immediately get thrown into mail, with your message displaying
and at the ? prompt type:  !sh   "Look ma, I'm root!"

Security problem #2:

A lot of people keep "tutor" with no password and widely distribute their
dialup number.  Tutor, a non-expert user, can't run the shell?! Or can they?
Create a file in the Filecabinet, editor either "vi" or "ed" and do a ":!sh"
in vi or "!sh" in ed, and wha-la!

Security problem #3:

Mail setup... UUCP phone numbers and passwords in the L.sys file are normally
protected so that NON-SUPERUSER people cannot hack them!  Go into mail setup
(any user... even Tutor) and you can get all the necessary hacking information!
Bad!!!!

Any others would be appreciated!!

					-Lenny

-- 
Lenny Tropiano               ...seismo!uunet!swlabs!godfre!quincy!lenny  -or-
American LP Systems, Inc.           ...cmcl2!phri!gor!helm!quincy!lenny  -or-
1777-18 Veterans Memorial Hwy.   	          ...mtune!quincy!lenny  -or
Islandia, New York 11722     +1 516-582-5525 ...ihnp4!icus!quincy!lenny

sean@killer.UUCP (09/24/87)

In article <54@quincy.UUCP>, lenny@quincy.UUCP (Lenny Tropiano) writes:
> Security problem #2:
> 
> A lot of people keep "tutor" with no password and widely distribute their
> dialup number.  Tutor, a non-expert user, can't run the shell?! Or can they?
> Create a file in the Filecabinet, editor either "vi" or "ed" and do a ":!sh"
> in vi or "!sh" in ed, and wha-la!
> 

	This one's easy:  assign tutor a password! :-)

	There is also another way for tutor to get a shell.  While in Office
of tutor the user has only to type /bin/sh or /bin/ksh, and the User Agent will
run the shell.  This works for ANY user not having "EXPERT" status.  The pass-
word solution will keep unwanted folks from getting in as tutor, but I dunno
how one would prevent this security problem once tutor has logged in success-
fully.

> Security problem #3:
> 
> Mail setup... UUCP phone numbers and passwords in the L.sys file are normally
> protected so that NON-SUPERUSER people cannot hack them!  Go into mail setup
> (any user...even Tutor) and you can get all the necessary hacking information!

	My solution here was to edit /usr/lib/ua/Administration.  Remove any
entries from this file that you don't want everyone using, and put them in
the install login's personal Administration file (/u/install/Administration).
In fact, the only things I left in /usr/lib/ua/Administration are "Changing
Password" and "System Information"; I moved the rest to install's Administra-
tion.  As an extra measure of security on L.sys (or Systems, as the case may
be) I set the permissions to 640.  If you do this you'll have to change the
file's group to mail, so that the AT&T Electronic Mail software can read it.

							Sean