Security Basics mailing list archives
Re: RDP over the internet
From: Thugzclub Thugzclub <thugzclub () googlemail com>
Date: Wed, 21 Mar 2012 16:51:30 +0000
On 19 March 2012 18:52, Ansgar Wiechers <bugtraq () planetcobalt net> wrote:
On 2012-03-19 Dan Lynch wrote:New vulnerabilities will be discovered every now and then. Duh. The question is: do they get fixed in a timely manner?The fact is that "open port" is a potential attack vector because a vulnerability may be discovered in the application.I'm sorry to have to break this to you, but as long as you're using TCP/IP you need an open port if you want to be able to establish a connection.But it's clear that *any* open port represents additional risk. If that open port is not required for the function of the system (as terminal services/RDP generally is not), it's an unnecessary risk (however convenient it might be). And that risk is compounded if that port is running by necessity with system level permissions, and offering up a login screen that people use with their admin credentials. Also, terminal services is dependent on the loading of yet another service: RPC.
This is my point exactly - any port represent an attack vector. This is not to say that you should not have open ports (you cannot operate without ports), but rather, you should congnisant of the fact that if a vulnerability is identified in the listening application, you may be vulnerabile. Software restrictions solutions (i.e AppLocker) are not a panacea, but they CAN protect you to a certain extent. The article from SANS provide a "good" (not comprehensive) analysis of their limitations: http://www.sans.org/reading_room/whitepapers/sysadmin/application-whitelisting-panacea-propaganda_33599 Its correct that assuming the RDP service is running in the context of system and is exploited by malware, you are truly buggered. However you can mitigate this by employing least privileges. RDP should be running in the local context (not Domain Admin or System) with the minimum set of privileges required. But you cannot stop there, if using Windows, look at DEP for buffer overflow protection and a reasonable HIPS. The key is defence in depth and this should be applied for all externally facing system.
For these reasons, I don't believe the concern expressed over exposing RDP to the internet is "a massive generalisation". I think that concern is clearly justified.Indeed. And I didn't write anything about "massive generalisation". I did, however, want to point out that one newly discovered vulnerability is no proof whatsoever for a claim about unpatched vulnerabilities.RDP is not of the same risk level as, say NTP.I'd argue that the complexity of VPN (or SSH) services is closer to RDP than to NTP, though. ;)And if, when we point out that risk, CEOs then see security officers as "the enemy", it's because the security folks have failed to (1) account for the value in the convenience offered by things like RDP, (2) reasonably evaluate that value against the risk, and (3) consider what actions, configurations and technologies are available to mitigate the risk.No argument there. And FTR: personally I do prefer using RDP through encrypted tunnels, even though RDP itself is an encrypted protocol. Regards Ansgar Wiechers -- "All vulnerabilities deserve a public fear period prior to patches becoming available." --Jason Coombs on Bugtraq ------------------------------------------------------------------------ Securing Apache Web Server with thawte Digital Certificate In this guide we examine the importance of Apache-SSL and who needs an SSL certificate. We look at how SSL works, how it benefits your company and how your customers can tell if a site is secure. You will find out how to test, purchase, install and use a thawte Digital Certificate on your Apache web server. Throughout, best practices for set-up are highlighted to help you ensure efficient ongoing management of your encryption keys and digital certificates. http://www.dinclinx.com/Redirect.aspx?36;4175;25;1371;0;5;946;e13b6be442f727d1 ------------------------------------------------------------------------
------------------------------------------------------------------------ Securing Apache Web Server with thawte Digital Certificate In this guide we examine the importance of Apache-SSL and who needs an SSL certificate. We look at how SSL works, how it benefits your company and how your customers can tell if a site is secure. You will find out how to test, purchase, install and use a thawte Digital Certificate on your Apache web server. Throughout, best practices for set-up are highlighted to help you ensure efficient ongoing management of your encryption keys and digital certificates. http://www.dinclinx.com/Redirect.aspx?36;4175;25;1371;0;5;946;e13b6be442f727d1 ------------------------------------------------------------------------
Current thread:
- Re: RDP over the internet, (continued)
- Re: RDP over the internet Banyan He (Mar 16)
- Re: RDP over the internet Melissa Augustine (Mar 16)
- RE: RDP over the internet Dave Wray (Mar 16)
- Re: RDP over the internet synja (Mar 17)
- Re: RDP over the internet David J2 (Mar 17)
- Re: RDP over the internet Ansgar Wiechers (Mar 16)
- Re: RDP over the internet Thugzclub (Mar 19)
- Re: RDP over the internet Ansgar Wiechers (Mar 19)
- RE: RDP over the internet Dan Lynch (Mar 19)
- Re: RDP over the internet Ansgar Wiechers (Mar 19)
- Re: RDP over the internet Thugzclub Thugzclub (Mar 21)
- Re: RDP over the internet Thugzclub (Mar 19)
- Message not available
- Re: RDP over the internet Ansgar Wiechers (Mar 19)