Re: NT/Exceed D.O.S.

[ap1 () TORCH ROWAN EDU (Andrew Pitman)]

Jamie,

Ditto for 6.1 on Win95.  Appears to be fixed in 6.1, among other bugs,
including an incompatibility with DEC Windows that was causing problems at
my shop.

Andrew
--
  "The wonderful thing about standards is that there are so
   many to choose from."
                                        (Andrew S. Tanenbaum)
+-----------------------------+---------------------------------+
| Andrew Pitman               | Management Information Systems, |
| Unix System Administrator/  | Technology Operations Support   |
|                   Webmaster |             at Rowan University |
+-----------------------------+---------------------------------+

On Thu, 29 Apr 1999, Jamie Lawrence wrote:

> I couldn't reproduce either effect with Exceed 6.1 under NTsp3.
> Everything behaved normally, both for new and existing sessions.
>
> -j
>
> At 01:57 PM 4/28/99 -0700, Matt Wilbur wrote:
> > Exceed (an X server, not an X emulator) version 6.0.1.0 on NT appears to
> > have fixed this problem, somewhat...
> >
> > Telnetting to port 6000 locks the server up for 20-30 seconds, but it
> > recovers eventually.  Not surprisingly, using netcat has the same effect...
> > although, contrary to Chris's findings with Exceed 5, I didn't need to send
> > any garbage characters, the connection alone did the job.  Also, it works
> > from any host, not just the one the xdm session had been initiated with,
> > regardless of host access settings in Xconfig, Exceeds "configuration" tool.
> >
> >
> > I'd still consider this DoS-bait, when you imagine a one-liner to
> > continuously connect to port 6000 of your favorite Exceed user's machine.
> >
> > Matt Wilbur
> >
> > [snip]
> > > This is regarding Hummingbird's Exceed X emulator v5 (and possibly v6)
> > > running on Windows NT.  I haven't tested Win95/98.
> > >
> > > The Exceed X server allows inbound TCP connections on port
> > > 6000 from the XDM> host.  If someone uses telnet from the XDM host to
> > connect to
> > > a PC running Exceed on port 6000 and enters any garbage text, the X server
> >
> > > will hang and the Exceed session is frozen for good.
> > >
> > > I have notified Hummingbird via their tech support web site
> > > but have not received a response yet.
> > >
> > > Chris LaFournaise
> > > cjlafournaise () escocorp com