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From: Yanek Korff (yanekcigital.com)
Date: Wed Nov 14 2001 - 10:27:48 CST

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    > Checkpoint does crash when being portscanned. Well, sort of.
    > Quite simply, when a (stateful) firewall, has too many
    > entries in the state table (IE it's full) then the box has problems.
    > In the case of checkpoint (or at least, this was the case a
    > few versions ago) it will crash. (And incidentally, if you are
    > synchronising the state table with another firewall for the purposes
    > of failover, thenthey'll both crash).
    > IIRC about 25000 connections will do this (less if you are using NAT)
    > Checkpoint also holds the 'state entries' for 50 seconds after the
    > connection is closed (IE FIN packets are seen), so you have a while to
    > reach the magic number.
    >
    > My experience was with a Nokia IP440/Checkpoint
    > Firewall-4.1SP3, but it sounds as if the same situation may
    > be occuring.

    Unfortunately, I don't think this is the case. If a table were being filled
    up, I'd expect the FW to stay up for some period of time before eventually
    crashing. Here are some relevant facts:

    1. Linux FW crashes -immediately- before it has the opportunity to log a udp
    packet with tcpdump
    2. Scans complete successfully against NT 4.0 and Solaris-x86

    -Yanek.