Tag Archive for: security

KB2992611 Breaks More than Web Servers

17 Nov 2014
November 17, 2014

This will be a short’ish post because I’m still trembling from the trauma…

I applied Windows Updates to a client’s production servers yesterday morning. Normally I wait an extra week to give things a chance to “shake out” and get tested in Dev (and other client’s servers) before I apply updates to production, but this time I saw KB2992611 in the announcements and wanted it installed ASAP.

This security update resolves a privately reported vulnerability in the Microsoft Secure Channel (Schannel) security package in Windows. The vulnerability could allow remote code execution if an attacker sends specially crafted packets to a Windows server.

Things were fine yesterday (low load) but once the load started ramping up today the web server was pretty much at 100% CPU – most of it in LSASS.EXE. Everything was very slow and painful. Lots of research, hours of trial and error – including rolling back yesterday’s updates – to no avail. Very frustrating.

As spirits were plummeting, Hans, the client’s resident genius, found this “Microsoft does it again” article. We then realized we should be removing this patch from ALL tiers of the application, not just the front-end. Removed it from the database server and middle app server and then the web server’s load dropped back to normal range. Time for a beer.

Moral of the story? Don’t always focus on the server with high CPU. Look at all the dependencies, especially when you know/suspect you have a bad update in the mix.

Java: Suppress Sponsor Offers

25 Aug 2014
August 25, 2014

While it is popular and common to suggest that we should avoid installing Java if we’re security conscious – or at least not enable it in our browsers – sometimes that’s just not an option. For instance, the web application that I spend my days in needs Java to be fully functional.

Java upgrades are a drag. One of the worst aspects has been to remember to uncheck the current sponsor stuff. Nope, I don’t need an Ask Toolbar and I really don’t want MacAfee Security Center installed. Ever!

If you feel the same way, you will love this new option at the bottom of the Advanced tab in the Java Control Panel:

Suppress sponsor offers when installing or updating Java

That’s pretty great.  You can find the Java Control Panel in your Windows Control Panel. If running Windows 8 or 8.1 just hit the windows key and type Java Control and search will turn it up as well.

Enjoy!

A Quick Look at IIS Crypto

22 Apr 2014
April 22, 2014

For many years now – I think about a decade — I have been building and managing Windows Web servers for a SaaS company. First as a contractor, then an employee and most recently as a consultant (tip: relationships matter). While I don’t have it down to an automated science, I do have pretty detailed checklists that I run through as part of each build.

My goal has always been to keep the server configurations consistent yet adapt as each new Windows Server release comes out. My first checklist was for a Server 2000 build. The one I updated last week was for 2012 R2. That’s covering some serious territory.IIS has certainly changed a lot over the years.

Of course, a big part of the builds revolves around security. One aspect of security is managing the SSL protocols and cipher suites offered by IIS. And, more importantly, which ones you do not wish to offer. I’ve documented this over the years and done some automation with batch files, vbs files (I know, I know…) and even .reg (registry import) files.

As I was updating the most recent servers last week I thought I had better do some quick research and make sure my notes were still current. These things date back 5 – 10 years after all. For instance, I know just half a year ago we went through the servers and disabled RC4 at Microsoft’s suggestion. That was never folded into my build notes…

While looking for SSL security updates I stumbled over a very handy little utility: IIS Crypto. I downloaded the tool, tried it on a dev server and then hit it with an external Qualys scan. It worked great – and fixed up a few holes that I had incorrectly plugged over the years (whoops). Now IIS Crypto is part of my toolbox.

IIS Crypto Screenshot

Just download and run it on your web server and choose the “Template” that applies. For me, that’s Best Practices with one click, then a second click to disable RC4 128/128 just to be consistent. Hit apply, schedule a reboot and you’re in good shape. Need to be PCI or FIPS compliant? Those are templates there as well.

There’s even a quick way to scan yourself from Qualys SSL labs.

Very slick. Highly recommended.

From their site:

IIS Crypto is a free tool that gives administrators the ability to enable or disable protocols, ciphers, hashes and key exchange algorithms on Windows Server 2003, 2008 and 2012. It also lets you reorder SSL/TLS cipher suites offered by IIS, implement best practices with a single click and test your website.

LastPass on Android Now Logs Into Mobile Apps

28 Mar 2014
March 28, 2014

Best new feature ever. This makes LastPass so much easier to use on the tablet.

(This is a link post — click the title of this article to get to the article it references).