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- VIRUS-L Digest Tuesday, 14 Feb 1989 Volume 2 : Issue 47
-
- Today's Topics:
- Valetine's Day trojan horse (VAX/VMS)
- Re: Valentine's Day VTxxx trojan horse mail message (VAX/VMS)
- VIRUS-L LISTSERV files now available via anonymous FTP
-
- ---------------------------------------------------------------------------
-
- Date: Tue, 14 Feb 89 11:21 EST
- From: Cincinnati Bengals. <KUMMER@XAVIER.BITNET>
- Subject: Valetine's Day trojan horse (VAX/VMS)
-
- This rumor is an obvious attempt to capatilize on the virus
- hysteria and cause people to be afraid to do anything on the computer.
- I'd be willing to bet money that it's impossible that when a mail
- message is read, the message causes files to be deleted. Either the
- rumor was improperly relayed, or someone is trying to cause fear in
- VAX/VMS users all over by spreading an absolutely absurd rumor.
-
- Tom Kummer
-
- ------------------------------
-
- Date: Tue, 14 Feb 89 13:10:16 est
- From: Stuart Labovitz <labovitz%etd2.dnet@wpafb-avlab.arpa>
- Subject: Re: Valentine's Day VTxxx trojan horse mail message (VAX/VMS)
-
- In order to get some "expert" opinions on this virus/trojan alert, I
- forwarded a copy of the VALERT message to the Info-VAX mailing list
- (Info-VAX@KL.SRI.COM). Jerry Leichter has responded directly to
- VIRUS-L, but appended below is another response (refering to Jerry's
- message) from Stephen Dowdy. I will forward any other relevant
- responses on to VIRUS-L, as well.
-
- LT Stuart L Labovitz
- USAF Electronic Technology Laboratory
- arpa: Labovitz%Etd2.decnet@Wpafb-avlab.arpa
-
- I bark, therefore I am.
- --Descarte's dog
-
- = = = = = = = = = = message from Stephen Dowdy follows = = = = = = = = = = =
-
- LEICHTER@VENUS.YCC.YALE.EDU ("Jerry Leichter ") writes:
-
- ] The rumor is that a Valentine's Day message has been prepared
- ] that has the potential for causing lots of personal (and operational)
- ] havoc. Any user who reads this message, on a VAX system, using a
- ] standard DEC terminal, will have all of his files deleted. This
- ] little nastygram is rumored to also put a sweet message and heart on
- ] the screen while doing its dirty work. A nice touch.
- ]
- ]This "rumor" is a wonderful example of a kind of "denial of service"
- ]virus. It infects the "wetware" of susceptible users. Different
- ]forms of this rumor have been floating around for several days now;
- ]they've been passed around internally to DEC, for example.
- ]
- ]There is NO truth behind this rumor. What it describes is
- ]impossible, ...
-
- (there is a lot of truth to the concept. DO NOT BLOW THIS OFF AS
- IMPOSSIBLE)
-
- ] a) The VMS MAIL program filters out escape and control sequences
- ] when presenting mail to the user. Even if there were a
- ] sequence which could cause damage, it can never reach the
- ] terminal as long as you use only READ to look at the message.
-
- VMS Mail did not always filter out control characters. I remember
- reading (in 3.7 i believe) a mail file of the famous Champagne Glass
- Line drawing set animation.
-
- ] b) A message COULD suggest that you type EXTRACT TT:, which would
- ] copy the message unfiltered to your terminal. This trick
- ] is often used to send, say, ReGIS pictures through the mail.
- ] Obviously, this is a deliberate action - you have to be wil-
- ] ling to do it. Just on general principles, you should NOT do
- ] this with a message from someone you don't know.
- ]
- ] A message could also tell you: Type EXTRACT FOO.COM, CTRL/Z,
- ] and @FOO. If you go ahead and do that, you will create and
- ] execute a command file which could do anything at all.
- ]
- ] Then again, the message COULD tell you "Shoot yourself in the
- ] head".
-
- Then again, the people who are hit by this form of trojan horse are not
- generally computer literate. If the message does say
- EXTRACT/NOHEAD FOO.COM
- the user *WILL* do it.
-
- ] d) UDK's (User Defined Keys) are a slightly different story. You can
- ] load them from the host but:
- ]
- ] 1. It is impossible for the host to force the terminal to
- ] send the contents of a UDK - you must deliberately
- ] type SHIFT with a function key to get the value sent.
- ]
- ] 2. When you load UDK's, you may ask the terminal to "lock"
- ] them. Once the UDK's are locked, any further attempts
- ] load them are ignored. Nothing the host sends can
- ] unlock the UDK's - it can be done only from SETUP or
- ] by power-cycling the terminal.
- ]
- ] If you don't use UDK's, (1) should protect you. If you DO use
- ] UDK's, (2) can protect you (though you have to make sure you
- ] lock the definitions).
-
- Ah, but again, the kind of user who falls for this type of trojan
- horse is not literate enough to know these things. It doesn't matter
- how many ways there are to divert mal-intented individuals, the common
- user is not going to use them. (and *someone* will have to restore
- their files, or the OS if the person has privs)
-
- ] In any case, on the VT330 and VT340, there is a SETUP option
- ] which disables block mode, so this becomes a non-issue.
-
- (once again... Joe User may not even know how to use SETUP.)
-
- ] I have no particular compatibles in mind here - there may not
- ] actually BE any which have made this kind of change. But to
- ] be safe, you have to be wary. I'd be ESPECIALLY wary of ter-
- ] minal emulation programs running on PC's - they often have the
- ] opportunity to provide all sorts of nifty, but dangerous,
- ] features which the hardware manufacturers find too expensive
- ] to include.
- ] -- Jerry
-
- Back in the days of 4.2 BSD Unix, when the ttys weren't protected by
- group ownership 'ttys', i wrote a program exploiting a "feature" of
- the Televideo 912/910 that allowed one to write to a user's terminal
- (in BSD, if they had MESG Y), and have the terminal send that command
- back. Needless to say, any person with mesg y, and root on a tvi was
- asking the system to go down. (i never use any of these things for
- malicious purposes, just to get the point across to people that there
- are *MANY* non-obvious ways to break security).
-
- Though, i agree that this reported trojan horse is probably not real,
- in it's reported form, it is *VERY* real as a general security issue.
- If i download your keys with a string, and you press that key, you're
- are in trouble. And no amount of convincing is going to make
- non-knowledgable users do what they should (lock keys, reset the
- terminal before logging in...; heck, i don't even do these things,
- since it is such a pain)
-
- Take a word of caution from the message. It is possible to do these
- things. (and though i would really like to make my process name in
- double wide characters for show users, i understand DECs approach to
- dropping out control characters, it is probably the correct approach
- in dealing with overly-"smart" terminals)
-
- - --stephen
- - --
- $!#######################################################################
- $! stephen dowdy (UNM CIRT) Albuquerque, New Mexico, 87131 (505) 277-8044
- $! Usenet: {convex,ucbvax,gatech,csu-cs,anl-mcs}!unmvax!charon!sdowdy
- $! BITNET: sdowdy@unmb
- $! Internet: sdowdy@charon.UNM.EDU
- $! Team SPAM in '87! SPAAAAAAAAAAAAAAAAAAAAMMMMMMM!
- $!#######################################################################
-
- = = = = = = = = = = message from Stephen Dowdy ends = = = = = = = = = = = =
-
- ------------------------------
-
- Date: Tue, 14 Feb 89 14:06:35 est
- From: ubu!luken@lehi3b15.csee.lehigh.edu
- Subject: VIRUS-L LISTSERV files now available via anonymous FTP
-
- Internet (including ARPAnet, MILNET, NSFNET, etc.) users can now
- access the VIRUS-L archives and backlogs via anonymous FTP to
- IBM1.CC.LEHIGH.EDU.
-
- Once logged in, issue a CD (or CWD) command to connect to either
- VIRUS-L (for the log files) or VIRUS-P (for the archive programs).
- At that point, the standard GET command will retrieve files, and the
- DIR command will list available files.
-
- The anonymous FTP is very new on our VM/CMS machine, so please report
- any problems to me. We currently know of some quirks when FTPing from
- Sun workstations - it takes several commands before anything happens.
- It has successfully been tested from other machines, however,
- including VAX/VMS (CMU TCP/IP) and Zenith PCs (NCSA TCP/IP).
-
- I hope that this adds to the functionality of the forum somewhat, even
- though loading files onto the LISTSERV filelist is still as difficult
- as ever...
-
- Ken van Wyk
-
- ------------------------------
-
- End of VIRUS-L Digest
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