"Setting these to no-execute does not allow the attacker to execute code on your system". It depends, with /lib/ld-linux.so.2 /tmp/script or bash /tmp/script.sh

"Setting these to no-execute does not allow the attacker to execute code on your system". It depends, with /lib/ld-linux.so.2 /tmp/script or bash /tmp/script.sh it may be possible to execute code on a noexec /tmp . As you said, setting noexec still helps preventing automated attacks.