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From: Mike Fedyk (mikefMATCHMAIL.COM)
Date: Tue Mar 13 2001 - 01:06:34 CST

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    On Mon, Mar 12, 2001 at 03:53:34PM -0600, Solar, Eclipse wrote:
    > Quoted from http://www.guardent.net/pr2001-03-12-ips.html
    >
    > > Waltham, MA -- March 12, 2001 -- Guardent, Inc., the leading
    > > provider of security and privacy programs for Global 2000
    > > organizations, today released new information regarding a
    > > significant weakness in many implementations of the
    > > Transmission Control Protocol (TCP) that affects a large
    > > population of Internet and network-connected devices.
    > >
    > > Tim Newsham, a senior research scientist at Guardent,
    > > discovered a method by which malicious users can close
    > > down or "hijack" TCP-based sessions on the Internet or
    > > on corporate networks. The research, titled "ISN Prediction
    > > Susceptibility", exposes a weakness in the generation of
    > > TCP Initial Sequence Numbers, which are used to maintain
    > > session information between network devices.
    > >
    > > Prior to Guardent's discovery, it was believed that TCP
    > > sessions were sufficiently protected from attacks by the
    > > random generation of initial sequence numbers. It is now
    > > known that these numbers are guessable on many platforms,
    > > with a high degree of accuracy. The ability to accurately
    > > guess sequence numbers, combined with readily available
    > > session information, allows for a variety of sophisticated
    > > attacks on computer networks.
    >
    > It seems that Guardent claims that the pseudo-random ISN
    > generation algorithm implemented in most TCP/IP stacks
    > is flawed. Does anybody have more information about this?
    >
    > Solar Eclipse

    Yep, and how long has this been known?? Years! He's probably talking about
    windows, because it has the largest percentage of packets on the internet.

    Mike