What is “ALL ALL=!SUDOSUDO” for?

Question

The last line of the /etc/sudoers file is:

grep -i sudosudo /etc/sudoers
Cmnd_Alias SUDOSUDO = /usr/bin/sudo
ALL ALL=!SUDOSUDO

why? What does it exactly do?

SUDOSUDO is probably an alias. Does it exist elsewhere in the file?
is "ALL ALL=!SUDOSUDO" as the last line is like when having DROP iptables POLICY and still using a -j DROP rule as last rule in ex.: INPUT chain? :D or does it has real effects?
I'm not 100% sure, but I believe it only prevents anyone from running sudo sudo ....

Mark Cohen · Accepted Answer · 2012-12-06 17:03:41Z

up vote 3 down vote accepted

That is to prevent someone from running sudo sudo, but it's not very effective.

It is easily circumvented by copying the sudo binary to another location. for example: cp /bin/sudo /sbin/sudo; sudo /sbin/sudo su -.

Best thing to do is not allowing "root ALL=(ALL) ALL"

answered Dec 6 '12 at 17:03

Mark Cohen
62810

	"Best thing to do is not allowing "root ALL=(ALL) ALL"" - is this line OK? – gasko peter Dec 7 '12 at 6:38
	can you Please post a real life example for this "not being effective" in the answer? – gasko peter Jan 23 at 17:42
	Why would somebody want to disallow running `sudo` with `sudo`? – Evan Teitelman Apr 10 at 13:01

1 Answer