Microsoft recently published the following support articles:
RC4 cipher is no longer supported in Internet Explorer 11 or Microsoft Edge
Windows Update has deprecated support for the RC4 cipher
Which is helpful when a customer rings up and says:
I can’t connect to xyz website.
Google and Mozilla dropped RC4 support at the start of 2016.
In short, go to http://www.mcafee.com/apps/downloads/security-updates/security-updates.aspx and download the DAT file. The install switches are as follows:
Which seems much easier than following McAfee’s instructions here:
How to manually update the DAT files for VirusScan Enterprise 8.x
Welcome, strangers, to the show
I’m the one who should be lying low
Saw the knives out, turned my back
Heard the train coming, stayed out on the track
In the middle, in the middle, in the middle of a dream
I lost my shirt, I pawned my rings
I’ve done all the dumb things
– Paul Kelly, Dumb Things
Microsoft AppLocker is a wonderful technology which allows your IT Department to prevent malicious programs from being run on your work computer. Great in theory, and my experience is that it works with some wrinkles. It broadly works by using Group Policy to configure what is a “Trusted” location.
Applocker and Active Setup
Active Setup allows you to execute commands once per user, early, during login. For example, you might want to do this to configure iTunes for each user who logs onto the computer.
Each Active Setup command has a file path to the commands that you need to run. If you don’t trust this file path in Applocker, your Active Setup fails.
If you are using System Center Configuration Manager (SCCM), then it’s likely that you’ll see this failure.
If you are going to add a “Path” rule to fix this issue, you need to add two. One for EXEs and another one for MSIs.
Removing AppLocker via Group Policy
So for whatever reason, you have a class of “”special”” computers which AppLocker is not to apply to. So you remove the AppLocker Group Policy from the “”special”” computer. And it still seems to have AppLocker blocking programs.
Well what seems to be happening is this:
- The AppLocker Application Identity service (AppIDSvc) is set to Manual.
- The AppLocker registry settings are being left behind.
- AppLocker causes applications to be blocked.
- Start the Application Identity service (AppIDSvc)
- Logon to the computer.
- Restart the computer.
This causes AppLocker to finish removing the registry settings.
Just before Windows XP gets to take a well earned retirement on “the farm”, it popped it’s ugly head up this week with an end user complaining we did something to break their new website
On purpose no less.
It seems IE8/Windows XP was receiving the wrong HTTPS certificate.
Upon investigation, I realised that the issue was that IE8 on WinXP does not support SNI.
Server Name Indication allows a web browser to tell a web host what site it is connecting to. (A web host can host multiple web sites …). The reason why a browser needs to tell the web host it connects to, is so the web browser gets the right HTTPS certificate.
If the browser does not support SNI then the browser will get the default web host certificate. Which may cause certificate errors to be displayed in the browser.
To prove that it was a lack of SNI support causing the issue, I used the excellent Qualys SSL Labs SSL Server Test tool.
I suggested to the customer that they use an alternate web browser, until they can replace Windows XP.
We’re in the process of developing a new Windows 8.1 SOE for a customer. One of the things I looked at was Internet Explorer HTTPS transmission security. Out of that, one of the things I recommend is enabling TLS 1.2.
TLS 1.2 – Configure Internet Explorer to use TLS 1.2 by default.
Transport Layer Security is how web browsers* communicate over the Internet. The current version, TLS 1.2 has a number of security enhancements & protection mechanisms over previous versions. Enabling it is, not only a Microsoft recommendation, but a good thing. Internet Explorer will fail back to older TLS versions if the web site doesn’t support TLS 1.2.
You can enable TLS 1.2 support via Group Policy or directly via Internet Explorer –> Internet Options –> Advanced –> Security.
How do I test that Internet Explorer is using TLS 1.2?
If the webpage reports under the “Further Information” heading that “This connection uses TLSv1.2 with …”, then you have enabled TLS 1.2.
- How’s My SSL? If, under the Version heading, it says TLS 1.2, then you’re using TLS 1.2.
What about other web browsers?
No. You’ll need to configure each web browser to support TLS 1.2. Some have better TLS support than others.
How do I tell whether a website supports TLS 1.2?
Use SSL Configuration Checker to test the website.
What if my web host tells me to disable TLS 1.1 or TLS 1.2?
”Run!”, would be my first thought. Your web host is telling you that they are not interested in providing a secure website.
Security Advisory 2868725: Recommendation to disable RC4
Microsoft MSDN Blog – Support for SSL/TLS protocols on Windows
Disabling TLS/SSL RC4 in Firefox and Chrome
RC4 in TLS is Broken: Now What?
IE11 Automatically Makes Over 40% of the Web More Secure While Making Sure Sites Continue to Work
SSL Pulse – Survey of the SSL Implementation of the Most Popular Web Sites
* amongst other things.
“What the security bulletin doesn’t say is that the change in Windows Installer repair operations means that application repair attempts will be met with a User Account Control credential window each time. However, the credentials required are administrator access.”
– Bug or Feature? KB2918614 Alters Windows Installer Behavior
Should your application install use Active Setup, to say, personal per-user settings, then this MS14-049 security patch causes a UAC prompt as well.
The current workaround, courtesy of happysccm, is as follows:
- Uninstall the application and reinstall it with the security update installed. (sourcehash file generated with security update)
- Manually copy the sourcehash file to c:\windows\installer folder. As the sourcehash file is generated based on the application files, the sourcehash file generated on computer A can be used on computer B.
Not scalable if, say, you have 500 packaged applications deployed to customers.
Recently went to a talk by Victoria Police Chief Forensic Scientist, Bryan Found PhD, titled “Forgeries, Fakes and Forensics”.
Bryan Found is a very engaging presenter. Things I found of interest, in no particular order:
- You can sign your signature with different parts of your body.
Which is to say the mechanical motions to write your signature can be used by your foot, or your bum.
- In one security role I held, the mantra was “burn the paper, and then stir the ashes”.
As burnt paper can be coated to stop it disintegrating, and the burnt writing can then be read.
- All photocopiers now print a digital watermark, which can be used to identify the photocopier, and the time and date of printing.
Printer manufacturers will extend this to all printers over time.
- Think using a black marker to react lines in your diary will make the original text unreadable? Think again…
- The devices used to reassemble shredded paper files are called “graduate trainees”. 🙂