[FD] Redhat/CentOS root through network-scripts

[Victor Angelier CCX <vangelier@xxxxxxxxxxx>]

Hi there,

Just found an issue in Redhat/CentOS which according to RedHat security team is 
not an issue. I don't know, sounds weird to me.

If, for whatever reason, a user is able to write an ifcf-<whatever> script to 
/etc/sysconfig/network-scripts or it can adjust an existing one, then your 
system in pwned.

Network scripts, ifcg-eth0 for example are used for network connections. The 
look exactly like .INI files. However, they are ~sourced~ on Linux by Network 
Manager (dispatcher.d).

In my case, the NAME= attributed in these network scripts is not handled 
correctly. If you have white/blank space in the name the system tries to 
execute the part after the white/blank space. Which means; everything after the 
first blank space is executed as root.

For example:

/etc/sysconfig/network-scripts/ifcfg-1337

NAME=Network /bin/id  <= Note the blank space
ONBOOT=yes
DEVICE=eth0

Yes, any script in that folder is executed by root because of the sourcing 
technique. Ex: . /etc/sysconfig/network-scripts/ifcfg-1337
Me as a developer, I don't really get why you want to do it like this. Its just 
<~>

So, if a use manage to get his hands on any of these files your box is gone. 
Protect them with your life.

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