BreachBytes

An article written by my partner Ben Uphoff has been published by (IN)SECURE Magazine. Scroll down to page 68 for the full text of the article.

Ben has done a great job of outlining what it takes to perform effective incident investigation using Net/FSE for in-depth alert analysis. I’d like to outline some of the snippets from the article that support the point that network intrusions, breaches and incidents are inevitable and the only way to perform proper incident investigation is to “keep it all.”

A core belief at Packet Analytics is that despite the best efforts of security vendors and practitioners, incidents are inevitable. There are simply too many threats and too many angles of attack. Technology on enterprise networks evolves so quickly that it is nearly impossible to keep up with the ever-changing threat landscape. For this reason, network breaches and security incidents must be seen as part of doing business in a connected world. Enterprises can mitigate the risk of a breach by following best practices and preparing a comprehensive incident response and recovery plan.

One challenge with working with network event data is that you can never be sure what event information is relevant until after the fact. For example, enterprises did not see value in storing DNS logs until DNS exfiltration attacks started appearing. With no historical log of DNS activity, those that fell victim to such attacks had no way of definitively knowing the extent of the data leakage resulting from the breach.

Contrary to the “keep it all” approach, SIMs try to reduce data volume at the collection points by aggregating similar events into statistical summaries that are then fed into the correlation engine, losing potentially valuable information in the process. Summaries are useful for the correlation engine but not for deep analysis of network events

We look forward to starting a dialog on the “keep it all” strategy and how we can improve the effectiveness of security and network operations in performing Network Event Analysis. Please post a comment.

There is a lot of talk right now about security for virtual machines. My post from last week was about a company generating NetFlow data from virtual switches. Now at least two significant efforts are being announced at RSA. First, Solera Networks is releasing a free beta of a virtual network tap. Their premise is that buying virtual equivalents of IDS, IPS, etc is wasteful and expensive to enterprises. The virtual tap interfaces with Solera’s line of packet capture devices and closes the gap in network visibility in virtual environments. This approach seems stronger than Montego’s approach (NetFlow only). Solera provides the entire packet stream allowing you to do pretty much anything.

The second big announcement is from IBM, who is announcing “Phantom”, a hypervisor security layer.  This layer will let admins in virtual environments lock down the virtualized environment outside the VM instances allowing a single point of configuration to lock down a host of virtualized servers or clients. This will be a technology to keep an eye on in the coming months.

As usual, the security industry is catching up with a technology (this time around VM) that has been around for a considerable amount of time. This attention to virtual environment security is welcome but as usual a bit late in the game. The securtiy industry  is still not keeping pace with technology advances. I don’t expect it to catch up anytime soon.

Most of my posts on BreachBytes are about using flow data, primarily NetFlow, for network security, incident response and network forensics on enterprise networks. I also tend to get rather technical most of the time. For this post I want to take a step back and answer the following question: what’s the big deal about network flow data? Let me try to answer this question in a single sentence:

“Network flow data, which can be generated by all enterprise routers, provides security analysts with real-time, long-term network visibility that can be used to prevent data leakage, defend against the insider threat and enhance incident response effectiveness.”

Key Points:

1. Generated by all enterprise routers: The technology is in place, your network can generate flow data in some form.
2. Real-time: Flow reporting can be near-real time depending on configuration.
3. Network visibility: Most enterprises are essentially blind to their internal network (the Soft Gooey Center — good in candy, bad in networks).
4. Long-term: Disk is cheap and flows are small, while still providing adequate information for a variety of network security tasks.

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In a previous post I gave a rundown of various software tools for collecting NetFlow data for use in network security incident response. NetFlow is pervasive in routers but another technology, sFlow, is nearly as prevalent in routers and can be collected from switches — an arena that NetFlow does not play in very much as of yet. sFlow is a packet sampling technology and can provide a depth of network visibility — a key component of network forensic and incident response — even beyond what NetFlow can offer. For more information on sFlow check out sflow.org.

There is not as much activity in free software with sFlow compared to NetFlow, however InMon has a great suite of tools that can help enterprises leverage sFlow data from routers and switches. Their sFlow Agent software can sniff packets off a network interface card and convert them into sFlow packets if you do not have a sFlow enabled switch or router but want to test what sFlow can bring to the table.

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Computer security is not a static field. Some people call it job security; others call it life with a beeper that goes off always at the wrong time. However, for a dynamic field the nature of the threats don’t seem to change that much. Back in the day, Script Kiddies earned their name and most were only interested in defacing web sites. Today, these same attacks are coming from a much more educated group, working in unison, to gain personal information or monetary goals. To compound the issue, technology is always changing. Our users demand these technologies in the name of productivity, (I hear a lot of the world’s major issues have been solved with bitTorrent) but early adopters usually get rewarded with the latest zero day attack. The one thing that hasn’t seemed to advance is the savvy of our end users. Phishing and email scams continue to grow because they continue to work.

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