defend from -> :() { :&:; } ;:

Bill Moran wmoran at
Mon Oct 22 09:13:24 PDT 2007

In response to Danielisz Laszlo <laszlo_danielisz at>:

> Please do not try to execute this: :() { :&:; } ;: on your BSD machine.

Why not?  It's just a fork() bomb.

> I ask all who already tried it how to defend from this?

Defend from what?  Make a policy that form() bombs are not funny and
launching them is grounds for account termination.  Then terminate the
account of anyone who does it.  Or put appropriate ulimits in place to
lessen the impact.

In any event, a user can bog down a system without launching a fork()
bomb.  If you don't have policies in place to delineate acceptable and
unacceptable behaviour, you'll have problems.

Bill Moran

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