Re: [CentOS] defense-in-depth possible for sshd?

2012-01-13 Thread Marc Deop
On Thursday 12 January 2012 18:56:04 Bennett Haselton wrote: Or is there a reason that an exploit against OpenVPN would be less powerful than an exploit against sshd? Not really. The thing is that the tools are there but you have to use them *CORRECTLY* The OpenVPN server and the SSH server

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-13 Thread Johnny Hughes
On 01/12/2012 08:56 PM, Bennett Haselton wrote: On 1/12/2012 5:25 PM, Johnny Hughes wrote: On 01/12/2012 10:31 AM, Tilman Schmidt wrote: Am 10.01.2012 19:05, schrieb Johnny Hughes: Limit access to the sshd port from only authorized places ... and the authorized places can be an openvpn type

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-13 Thread Gordon Messmer
On 01/10/2012 01:12 AM, Bennett Haselton wrote: What about sshd -- assuming that the attacker can connect to sshd at all (i.e. not prevented by a firewall), if they find an exploit to let them take control of sshd, would that imply immediate total control of the machine? Yes, but the question

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-12 Thread Tilman Schmidt
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Am 10.01.2012 19:05, schrieb Johnny Hughes: Limit access to the sshd port from only authorized places ... and the authorized places can be an openvpn type connection if you always need access from difference IPs. If you have a laptop, put an

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-12 Thread Les Mikesell
On Thu, Jan 12, 2012 at 10:31 AM, Tilman Schmidt t.schm...@phoenixsoftware.de wrote: I'm not convinced that would actually improve security. What that does is replace the risk of intrusion via an sshd exploit by the risk of intrusion via an OpenVPN exploit. Yes, but only to someone with

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-12 Thread Johnny Hughes
On 01/12/2012 10:31 AM, Tilman Schmidt wrote: Am 10.01.2012 19:05, schrieb Johnny Hughes: Limit access to the sshd port from only authorized places ... and the authorized places can be an openvpn type connection if you always need access from difference IPs. If you have a laptop, put an

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-12 Thread Bennett Haselton
On 1/12/2012 5:25 PM, Johnny Hughes wrote: On 01/12/2012 10:31 AM, Tilman Schmidt wrote: Am 10.01.2012 19:05, schrieb Johnny Hughes: Limit access to the sshd port from only authorized places ... and the authorized places can be an openvpn type connection if you always need access from

[CentOS] defense-in-depth possible for sshd?

2012-01-10 Thread Bennett Haselton
If an attacker finds an exploit to take control of httpd, they're still blocked in part by the fact that httpd runs as the unprivileged apache user and hence can't write any root-owned files on the system, unless the attacker also knows of a second attack that lets apache escalate its

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-10 Thread Adrian Sevcenco
On 01/10/12 11:12, Bennett Haselton wrote: What about sshd -- assuming that the attacker can connect to sshd at all (i.e. not prevented by a firewall), if they find an exploit to let them take control of sshd, would that imply immediate total control of the UsePrivilegeSeparation Specifies

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-10 Thread Bennett Haselton
On 1/10/2012 2:02 AM, Adrian Sevcenco wrote: On 01/10/12 11:12, Bennett Haselton wrote: What about sshd -- assuming that the attacker can connect to sshd at all (i.e. not prevented by a firewall), if they find an exploit to let them take control of sshd, would that imply immediate total

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-10 Thread John Doe
From: Bennett Haselton benn...@peacefire.org On 1/10/2012 2:02 AM, Adrian Sevcenco wrote: UsePrivilegeSeparation Specifies whether sshd(8) separates privileges by creating an unprivileged child process to deal with incoming network traffic. After successful authentication, another

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-10 Thread Bennett Haselton
On 1/10/2012 5:16 AM, John Doe wrote: From: Bennett Haseltonbenn...@peacefire.org On 1/10/2012 2:02 AM, Adrian Sevcenco wrote: UsePrivilegeSeparation Specifies whether sshd(8) separates privileges by creating an unprivileged child process to deal with incoming network traffic. After

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-10 Thread John Doe
From: Bennett Haselton benn...@peacefire.org On 1/10/2012 5:16 AM, John Doe wrote: The sshd child is running as bob; so it has bob (and not root) rights... Yes, I understand that.  What I said was that if you could take complete control of the sshd process you were connecting to, even if

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-10 Thread Bent Terp
On Tue, Jan 10, 2012 at 2:49 PM, John Doe jd...@yahoo.com wrote: From: Bennett Haselton benn...@peacefire.org On 1/10/2012 5:16 AM, John Doe wrote: The sshd child is running as bob; so it has bob (and not root) rights... Yes, I understand that. What I said was that if you could take

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-10 Thread Ned Slider
On 10/01/12 13:34, Bennett Haselton wrote: On 1/10/2012 5:16 AM, John Doe wrote: From: Bennett Haseltonbenn...@peacefire.org On 1/10/2012 2:02 AM, Adrian Sevcenco wrote: UsePrivilegeSeparation Specifies whether sshd(8) separates privileges by creating an unprivileged child process

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-10 Thread m . roth
John Doe wrote: From: Bennett Haselton benn...@peacefire.org On 1/10/2012 5:16 AM, John Doe wrote: The sshd child is running as bob; so it has bob (and not root) rights... Yes, I understand that.  What I said was that if you could take complete control of the sshd process you were

Re: [CentOS] defense-in-depth possible for sshd?

2012-01-10 Thread Johnny Hughes
On 01/10/2012 07:58 AM, Ned Slider wrote: On 10/01/12 13:34, Bennett Haselton wrote: On 1/10/2012 5:16 AM, John Doe wrote: From: Bennett Haseltonbenn...@peacefire.org On 1/10/2012 2:02 AM, Adrian Sevcenco wrote: UsePrivilegeSeparation Specifies whether sshd(8) separates privileges by