--dirs accepted any path and fed it to `find -delete` running as root,
with no confirmation: `--clean --dirs /home` removed every file in /home
past the age threshold, and `--dirs /` did it system-wide.
Now refuses protected directories, comparing the readlink -f resolved
path so a symlink or /tmp/../home cannot smuggle one through, and
requires absolute paths. Anything outside the /tmp,/var/tmp defaults
also needs an interactive confirmation -- or --yes, so unattended use
stays possible; without a tty and without --yes it refuses rather than
hanging in cron.
usage() sliced fixed line numbers (head -22 | tail -n +18) and had
already outgrown them, truncating --help mid-list at --age. So --dirs,
the one option that could destroy a system, was the one option --help
never mentioned. Replaced with a sed range that tracks the comment block
wherever it moves.
The first version of the protected-path check let "/" through: it
compared against "${p%/}", which turns the "/" entry into an empty
string that matches nothing. Caught by testing the guard against the
paths it exists to stop, rather than assuming it worked.
Both scripts built a command string by interpolating user input into
bash -c:
sudo -u zimbra bash -c "... -m '$EMAIL' ..."
The single quotes inside the double-quoted string are not protection --
the outer shell expands $EMAIL first. An address of
x' ; id ; echo '
closes the quote and runs arbitrary commands. Both scripts require root
and invoke this through sudo -u zimbra, so injected commands execute as
the account that owns the entire mail store. Verified against the exact
quoting pattern before and after the change.
Fixed by single-quoting the script body so nothing is interpolated, and
passing values as positional arguments. The bash -c wrapper is kept
deliberately rather than calling zmmailbox directly, since it may depend
on shell setup and this could not be tested against a live Zimbra.
Two related holes in the same input paths:
- $EMAIL is also part of the backup filename, so a "/" wrote outside
$BACKUP_DIR. Now validated as a plain address.
- The restore prompt took a filename and concatenated it into a path, so
"../../etc/shadow" escaped $BACKUP_DIR. Now rejects anything
containing a separator.
Also switched the backup listing from `ls | grep "$EMAIL"` to a find
with grep -F: unquoted the address was treated as a regex, so "." in it
matched any character.
jcoffey-dev
LINUXexpert.org