Apache DoS attack?

From: Micha³ Zalewski (lcamtufat_private)
Date: Tue Dec 30 1997 - 02:07:04 PST

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    [execuse me if it has been discovered before]
    
    Here's a simple exploit for Apache httpd version 1.2.x (tested on =
    1.2.4).
    When launched, causes incerases of victim's load average and extreme
    slowdowns of disk operations. On my i586 Linux annoying slowdown has =
    been
    experienced immediately (after maybe 5 seconds). After about 4 minutes
    work has been turned into real hell (286?).
    
    Attached program ('beck') is a shell script. It works by sending
    excessive http requests with thousands of '/'s inside (parsed from file
    'beck.dat'). Single request causes just a little longer thinking of
    Apache. But when requests are sent from a loop - huh, victim
    system becomes slower and slower... At least on my machine, maybe when
    Apache is running on a lightspeed workstation this script makes no
    difference.
    
    PS. Fast connection should help... All depends on victim's system
    performance.
    
    _______________________________________________________________________
    Michal Zalewski [tel 9690] | finger 4 PGP [lcamtufat_private]
    =3D--------- [ echo "while [ -f \$0 ]; do \$0 &;done" >_;. _ ] =
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