Experiment, on a Linux/UNIX system, with a version of the vulnerable shell script shown in Figures A and B, but using a small data file of your own. Explore changing first the PATH environment variable, then the IFS variable as well, and making this script execute another program of your choice

Figure A. #!/bin/bash user=`echo $1 |sed 's/@.*$//'` grep $user /var/local/accounts/ipaddrs Figure B

#!/bin/bash PATH="/sbin:/bin:/usr/sbin:/usr/bin" export PATH user=`echo $1 |sed 's/@.*$//'` grep $user /var/local/accounts/ipaddrs