[comp.virus] NetWare and Virus

WHMurray@DOCKMASTER.NCSC.MIL (07/27/90)

Well, we seem to have a problem here.

The posting by Jon David suggests that the virus executes on the
workstation, has no WRITE privilege to the server, but infects
programs on the server.  By private email to me, Jon confirms that
that is what he intended to say.  He describes to me the test that he
conducted; it sounds convincing.  He asserts that Novell
representatives have seen the demonstration.

On the other hand, the posting to this list by Novell clearly states
that the the workstation must have rights to write and modify the
file.

It seems to me that someone is in error.

If David is correct, then, not only do we have a small virus problem,
but we have a very large NetWare security problem.

It would be interesting to know whether the virus simply writes to the
server, or whether it contains some overt mechanism to disable,
subvert, or otherwise bypass NetWare security.

William Hugh Murray, Executive Consultant, Information System Security
21 Locust Avenue, Suite 2D, New Canaan, Connecticut 06840
203 966 4769, WHMurray at DOCKMASTER.NCSC.MIL

MALCOLM@tower-vax.city-poly.ac.uk (07/30/90)

In VIRUS-L digest V3 #132, William Hugh Murray writes:

> Well, we seem to have a problem here.
>
> The posting by Jon David suggests that the virus executes on the
> workstation, has no WRITE privilege to the server, but infects
> programs on the server.  By private email to me, Jon confirms that
> that is what he intended to say.  He describes to me the test that he
> conducted; it sounds convincing.  He asserts that Novell
> representatives have seen the demonstration.
>
> On the other hand, the posting to this list by Novell clearly states
> that the the workstation must have rights to write and modify the
> file.

Just a thought: during the test, is a user with supervisor rights
active on the network?  It would be *theoretically* possible for code
to put the LAN adaptor into promiscuous mode (on adaptors which
support this) and listen for a supervisor login request going past.
Equipped with this information it could then masquerade as supervisor.
It *may* also be possible for it to achieve the same end without
gleaning the username/password, by recognising a privileged connection
and then forging whatever the server uses to identify that connection
(though there'd doubtless be problems here with MAC-level addressing).

Either of these approaches is unlikely in a compact virus, though.

Disclaimer: I know very little about Novell protocols.  *Don't* take
this as an authoritative statement that they're insecure.  Hopefully a
genuine guru will tell me why it can't be done this way.

Regards,
Malcolm
- --
Malcolm Ray
City of London Poly Computer Service, 100 The Minories, London EC3N 1JY ENGLAND
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