Re: [cobalt-security] OT OpenSSH question

[Michael Stauber <cobalt@xxxxxxxxxxxxxx>]

Hi Rick,

> privilege separation was an issue that caused root compromise, IIRC. It was
> one of the last vulnerabilities of SSH. 

That's not entirely correct, but you're right that privilege separation was 
involved - as a work around which can limit the impact of a compromise of 
OpenSSH.

Some background info:

Usually the entire SSHd daemon runs as user root. So if someone manages to 
exploit SSH, then he can gain root access. With privilege separation only a 
small portion of SSHd runs with root permissions, while the majority of code 
runs with lesser privileges. It'll not stop exploits, but could manage to 
lessen the impact of exploits as an attacker will not end up with root access 
right away.

Privilege separation is a rather new feature in OpenSSH and it came up with 
release 3.3, but still had a few shortcommings back then. In the popular (and 
most recent) OpenSSH PKG packages for the Cobalt's privilege separation is 
enabled by default.

-- 

With best regards,

Michael Stauber