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DNS Knows. So Why Not Ask?

DNS is like the town gossip of the network infrastructure. Computers and apps ask DNS questions and you can ask DNS who has been asking to resolve malware domains. When internal trusted systems are using DNS to resolve the names of known malware sites, this can be an Indicator of Compromise and a warning to clean the potentially infected systems and block traffic to the domain.

Blacklisting the known malware domains using local RPZs, firewalls, Cisco IronPort Web Security Appliance (WSA), or Cloud Web Security (CWS) is a great way to add an extra level of security in organizations. But what if you are just getting started in the process of cleaning systems and just need some situational awareness? Or, how can you manually check to see if these devices are working as expected? How can you determine independently of security devices, and at any point in time, that client systems are not reaching out to malicious domains? You can use dig but this post focuses on a Python example. Let’s first take a look at some DNS mechanics.

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Check Ins – Why location needs to be part of Authentication and Identity

Dude, where’s my IP?

I love to check in on social networks like Foursquare and Google+. Most of the time, there’s no point to it, but it’s fun to see what friends and colleagues are up to or discover new local haunts. Despite the fun and games, location is much more important to the network than it appears. My physical location may have little or everything to do with my network location and there’s no reason for them to match exactly, but there are significant reasons to be more accurate.

You Are Here

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A Crypto Conversation: How We Choose Algorithms

Cryptography is critical to secure, trustworthy communications. Recent questions within the tech industry have created entirely new discussions about the cryptography underpinning our communications infrastructure. While some in the media have focused on the algorithm chosen for Deterministic Random Bit Generation (DRBG), we’ve seen many more look to have a broader crypto conversation. With this backdrop, I’d like to take the opportunity to talk about how we select algorithms (not just the DRBGs) for our products.

Before we go further, I’ll go ahead and get it out there: we don’t use the DUAL_EC_DRBG in our products. While it is true that some of the libraries in our products can support the DUAL_EC_DRBG, it is not invoked in our products. For our developers, the DRBG selection is driven by an internal standard and delivered to those developers from an internal team of crypto experts through a standard crypto library. The DRBG algorithm choice cannot be changed by the customer. Our Product Security Incident Response Team (PSIRT) confirmed this in a Security Response published on October 16.

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Practical Tips for Safekeeping your Mobile Devices

Now when I’m talking about safekeeping a mobile device, I’m not saying don’t use your Kindle by the pool or let your toddler play on the iPad while eating ice cream. These are dangerous things to be doing with a gadget, but today I want to focus more on the data within that device, rather than the device itself.

No matter what you do, your device may be stolen. It only takes a moment of inattention for someone to swipe your phone or tablet. Before that unfortunate event occurs, there are several things that you can do to mitigate the damage that occurs from the loss of a mobile device.
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One Week After April First, It’s No Joke

April first falls on a Tuesday next year. The following Tuesday is Microsoft’s monthly security update. It will be the last monthly security update for the Windows XP operating system. About one third of the computers with Windows operating systems on the Internet today are still running Windows XP, an operating system almost 15 years old. After the April 2014 update, issues with Windows XP will no longer be patched; Windows XP users should have already migrated to a more current Windows version. So with that we present, David Netterman’s Top Ten Security Related Reasons Why You Should Upgrade Your Computer’s Old Operating System:
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