For what it's worth, you can set /usr/local/bin/bash in /etc/shells then use that path so that if you upgrade bash to a new release you don't have to bother with updated /etc/shells and changing your user's shell.
For further actions, you may consider blocking this person and/or reporting abuse
Where hackers, sticks, weekend warriors, pros, architects and wannabes come together
For what it's worth, you can set
/usr/local/bin/bashin/etc/shellsthen use that path so that if you upgrade bash to a new release you don't have to bother with updated/etc/shellsand changing your user's shell.