[ISN] MS issues bum security patch, contradicts self

From: InfoSec News (isnat_private)
Date: Tue Oct 23 2001 - 00:35:42 PDT

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    By Thomas C Greene in Washington
    Posted: 22/10/2001 at 10:00 GMT
    Recently-issued patches for an exploitable RDP (Remote Data Protocol)
    bug in Win-NT and 2K have given users trouble enough for MS to yank
    one of them (details below). The timing is unfortunate. Only last week
    Microsoft Security Manager Scott Culp called on outside security
    researchers to follow Redmond's no-tell bug reporting example
    One core issue is exploit code, and the examples are Nimda and Code
    Red. "It's high time the security community stopped providing
    blueprints for building these weapons," Culp said.
    His aim is to keep exploitable data out of the hands of the Blackhat
    development community, which, while perfectly legitimate, is a fairly
    shaky proposition in practical terms. Blackhats are often well ahead
    of vendors, as we've seen many times.
    We certainly don't advocate broadcasting step-by-step exploit manuals
    -- especially by the mainstream press and by security vendors which
    stand to profit from abuse; but we believe that the tech press and
    independent security lists should continue to publish detailed
    information. We wish Microsoft would contribute the data they find, at
    least after a patch has been issued.
    We say this because system configurations vary and it's important to
    verify that a given patch actually does the job in each case.
    Withholding the information needed to prove that it works forces
    admins to trust that it does. This can produce a false sense of
    security, which is worse than incomplete security of which one is, at
    least, aware.
    For rigorous evaluation we need two things: a detailed description of
    the bug, and as many working exploits as we can find to run against
    the patch. Only then can we be confident that a patch is robust.
    "Without exploit code, how do we ensure that the patches actually
    work," VulnWatch http://www.vulnwatch.org moderator Steve Manzuik
    asked in a recent letter to Culp.
    "Trust our vendor? I don't think so. Vendors have proven that they bow
    to stock prices and market pressures and will continue to do this over
    and above security needs. Multiple vendors, not just Microsoft, have
    also proved that they will not completely research the issues
    themselves, and release insufficient patches," Manzuik says.
    Funny that 
    Talk about insufficient patches. MS concludes that the NT version of
    their RDP-bug patch can be installed safely, while the 2K patch will
    make a mess of your system and has been removed from the TechWeb site
    pending a fix.
    If you've downloaded the 2K patch and not yet installed it, then you
    should discard it before some well-meaning OFH ninny goes ahead with
    the installation for you.
    The patch is not crucial as the RDP hole can't (yet) be exploited in a
    destructive manner. A "particular series of data packets" will shut
    the server down, but a simple re-boot is all that's needed to bring
    things back. Of course, if one's being deliberately attacked with this
    vulnerability, re-booting every fifteen minutes pretty much equals a
    denial of service.
    The systems affected are: NT Server 4.0, Terminal Server Edition; 2K
    Server; 2K Advanced Server; and 2K Datacenter Server. The NT patch is
    available here
    bulletin/ms01-052.asp; and the 2K patch will be posted as soon as
    possible, MS says.
    It would be nice if MS would specify the 'particular series of
    packets' which triggers the RDP freeze, as it's quite possible there's
    a simple workaround which might be applied as a stopgap. It would also
    be nice to run an attack against one's own machine after patching, to
    ensure that the fix is effective on one's system.
    But that would require us to regard exploit code as a tool, not a
    weapon. Unfortunately it's both, which is why it may never be possible
    to reconcile these two quite legitimate, and eternally conflicting,
    points of view. 
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