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Here is another (less interesting) example of Apache DoS attack,
called 'beck2'. The only thing I want to show is very ineffective
management of memory, CPU time and other resources. This attack is
possible in two cases:
1. Attacker owns an account on a victim machine, or
2. Victim's directory structure is very deep (?).
When one of above statements is true, it's possible to perform a
remote attack, even when Apache has been already patched against
first version of 'beck'. More details can be deducted from
sources :)
In well-configured system, any kind DoS attack should be at least
ineffective (resources *required* to attack should be significally
larger than resources *affected* by attack ;). Unfortunately, it's
very, very easy to attack Apache servers using minimal amount of
time and brain resources :) Maybe it's time to rewrite larger parts
of code?
_______________________________________________________________________
Michal Zalewski [tel 9690] | finger 4 PGP [lcamtufat_private]
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