On Monday, April 06, 2015 03:02:20 PM Trevor Vaughan wrote: I'd say this is still the case. Tfpd and vnc are not universally needed. I think the aim is to reduce root running daemons (xinetd) in the common use case so that the attack surface is smaller. In your situation on RHEL6, install xinetd if you need it. In the case of RHEL7, systemd socket activation should work (should even be shipped that way). -Steve

I am guessing the verbiage would help with many other products as well. In the past with getting systems ATO, a developer/administrator/isso only had to document the delta’s of their configuration against the requirements and justify why they needed the delta. Programs, for example, like Nagios for enterprise monitoring uses xinetd. I am sure there are plenty of other programs that use it also. Does that rule or practice no longer apply?

That language always helps and should probably just be a preface to the whole guide. A written justification *should* always suffice. On Mon, Apr 6, 2015 at 5:12 PM, Shawn Wells <shawn(a)redhat.com&gt; wrote: -- Trevor Vaughan Vice President, Onyx Point, Inc (410) 541-6699 tvaughan(a)onyxpoint.com -- This account not approved for unencrypted proprietary information --

For what it’s worth, I agree with Trevor… the guidance from DISA is that if the service isn’t needed, turn it off, whether that’s TFTP or Apache. TFTP is small enough that it doesn’t require its own STIG like Apache, but there are still hardening guidelines for TFTP in the STIG, should you choose to use it. It does bug me a bit that there’s an explicit call to turn off TFTP in the STIG, but not one to turn off Apache. (Sure, the blanket “turn off unnecessary services” is there, but that should cover both TFTP and Apache equally, I would think. The current manifestation makes it look as though TFTP is somehow worse than apache.) I don’t see TFTP as being any different than using anonymous ftp or unencrypted http, as long as the architecture warrants the solution. In all my experience with accreditors, they will look at the threat and determine whether they agree on the residual risk. Keep in mind that PXE itself has intrinsic risks if implemented badly, but those risks can be reduced with good engineering and architecture practices. -- Tom Albrecht III, CISSP-ISSEP, GPEN Information Assurance Engineer Staff Cyber & Security Solutions Team (CaS2T) Lockheed Martin Corporation, IS&GS thomas.c.albrecht(a)lmco.com (m) 484-798-0109 (w) 610-354-7424 From: scap-security-guide-bounces(a)lists.fedorahosted.org [mailto:scap-security-guide-bounces@lists.fedorahosted.org] On Behalf Of Trevor Vaughan Sent: Thursday, April 09, 2015 5:37 PM To: Steve Grubb Cc: SCAP Security Guide Subject: EXTERNAL: Re: Xinetd, VNC, and TFTP VNC is not universally needed, I'll definitely agree on that one. But, I haven't seen many environments that *don't* use some sort of GUI forwarding, be it X (horrible, no), VNC, NXMachine, or something. Sometimes you just need an app "over there" and a SOCKS proxy won't cut it. But...how do you kickstart your systems from DHCP and/or update your network devices that only speak tftp? Reference: https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/... I cry foul on the fewer daemons make the attack surface smaller as I like risk analyses with my mandates. Xinetd *is* actually a security layer providing services for daemons that cannot be otherwise easily protected. Sure, it can be abused by a reckless admin, but what can't? Look at what some of the cloud services do with iptables and turning everything into forwarding routers! Yes, there are CVEs against xinetd, there are also CVEs against well, pretty much everything, and until another *vendor supported* solution exists, we need to use what is in the docs. Thanks, Trevor On Mon, Apr 6, 2015 at 3:16 PM, Steve Grubb <sgrubb(a)redhat.com&gt; wrote: On Monday, April 06, 2015 03:02:20 PM Trevor Vaughan wrote: I'd say this is still the case. Tfpd and vnc are not universally needed. I think the aim is to reduce root running daemons (xinetd) in the common use case so that the attack surface is smaller. In your situation on RHEL6, install xinetd if you need it. In the case of RHEL7, systemd socket activation should work (should even be shipped that way). -Steve -- Trevor Vaughan Vice President, Onyx Point, Inc (410) 541-6699 tvaughan(a)onyxpoint.com -- This account not approved for unencrypted proprietary information --