Case Study: Pro-active Log Review Might Be A Good Idea
Andrew Valentine January 14, 2013
With the New Year having arrived, it's difficult not to reflect back on last year's caseload. While the large-scale data breaches make the headlines and are widely discussed among security professionals, often the small and unknown cases are the ones that are remembered as being the most interesting from the investigators point of view. Every now and again a case comes along that, albeit small, still involves some unique attack vector - some clever and creative way that an attacker victimized an organization. It's the unique one-offs, the ones that are different that often become the most memorable and most talked about amongst the investigators.
Such a case came about in 2012. The scenario was as follows. We received a request from a US-based company asking for our help in understanding some anomalous activity that they were witnessing in their VPN logs. This organization had been slowly moving toward a more telecommuting oriented workforce, and they had therefore started to allow their developers to work from home on certain days. In order to accomplish this, they'd set up a fairly standard VPN concentrator approximately two years prior to our receiving their call. In early May 2012, after reading the 2012 DBIR, their IT security department decided that they should start actively monitoring logs being generated at the VPN concentrator. (As illustrated within our DBIR statistics, continual and pro-active log review happens basically never - only about 8% of breaches in 2011 were discovered by internal log review). So, they began scrutinizing daily VPN connections into their environment. What they found startled and surprised them: an open and active VPN connection from Shenyang, China! As in, this connection was LIVE when they discovered it.
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