This post is my 200th for HolisticInfoSec, and I mark it with particular consideration for the topic, coupled with profound recognition of the process that lead to this discussion.
As a graduate student enrolled in the SANS Technology Institute's MSISE program, I recently completed the Joint Written Project requirement.
My partners and I were assigned the topic Assessing Outbound Traffic to Uncover Advanced Persistent Threat.
Of my partners, I hold the highest regard; participating in this project with Beth Binde and MAJ TJ O'Connor was quite simply one of the most rewarding efforts of my professional career. The seamless, efficient, tactful, and cooperative engagement practiced throughout the entire 30-day period allowed for completion of the assignment resulted in what we hope readers will consider a truly useful resource in the battle against APT.
Amongst positions taken for this paper is a simple premise: there are tactics that can be applied in the enterprise to detect and defend against APT that do not require expensive, over-hyped, buzzword-laden vendor solutions.
Think I'm kidding about buzzwords and hype?
Following are real conversations overheard in the aisles at (ironically) the RSA Conference.
1) What is the ROI on your SEM, and will it detect any APTs on my LAN?
2) Does the TCO justify spend for a SaaS/cloud solution; you know, an MSSP?
3) Wait, what about APT in the cloud? If I use a Saas-based SEM to manage events on my cloud-based services, will it still find APTs?
All opportunities for chastisement and disdain aside, commercial solutions clearly are an important part of the puzzle but are far from preemeninent as the only measure of detection and defense.
Instead, Assessing Outbound Traffic to Uncover Advanced Persistent Threat, proposes that:
"Advanced Persistent Threat (APT) exhibits discernible attributes or patterns that can be monitored by readily available, open source tools. Tools such as OSSEC, Snort, Splunk, Sguil, and Squert may allow early detection of APT behavior. The assumption is that attackers are regularly attempting to compromise enterprises, from basic service abuse to concerted, stealthy attempts to exfiltrate critical and high value data. However, it is vital to practice heightened operational awareness around critical data and assets, for example, card holder data, source code, and trade secrets. Segment and wrap critical data within the deeper protection of well monitored infrastructure (defense in depth). Small, incremental efforts, targeted at protecting high value data value (typically through smaller and protected network segments), provide far greater gains than broader, less focused efforts on lower value targets. In a similar vein, layered defensive tactics (multiple layers and means of defense) can prevent security breaches and, in addition, buy an organization time to detect and respond to an attack, reducing the consequences of a breach."
This perspective is shared by Jason Andress, in his ISSA Journal cover article, Advanced Persistent Threat Attacker Sophistication Continues to Grow?
Jason's article fortuitously hit the wire at almost exactly the same time our paper went live on the STI site, as if to lend its voice the arguement:
"This paper discusses what exactly APT is, whether or not it is a real threat, measures that can be implemented in order to mitigate these attacks, and why running out to buy the latest, greatest, and most expensive security appliance might not be the best use of resources."
You will find consistent themes, similarly cited references, and further useful resource material in Jason's excellent work. I look forward to seeing more of Jason's work in the ISSA Journal in the future.
In closing, from our paper:
"Even the best monitoring mindset and methodology may not guarantee discovery of the actual APT attack code. Instead, the power of more comprehensive analysis and correlation can discover behavior indicative of APT-related attacks and data exfiltration."
If APT worries you as much as it seemingly does everyone, give the papers a read, take from them what suits you, and employ the suggested tactics to help reduce attack vectors and increase situational awareness.
Cheers and good luck.