Lessons Learned From The Ramnit Botnet Takedown

While most organizations won’t find themselves in similar circumstances, there are important takeaways they can apply to any security program.

Francisco Fonseca, CEO & Co-founder of AnubisNetworks

June 15, 2015

4 Min Read
Source: AnubisNetworks

In the security community, there is a popular adage that says, “It’s not a matter of if you’ll be breached, but when.” This statement is meant to remind us that our focus should not only be on preventing a breach, but must also include strategies to detect and remediate incidents when they occur.

The unfortunate fact is that despite this knowledge, most of the time organizations have no idea they have suffered a data breach or are under attack by hackers. When the source of the attack is finally identified, it’s often too late and the result is usually reputational harm and millions of dollars lost.

In a knowledge-driven era, data has become our worst enemy and biggest ally. Data can be the enemy when organizations are bombarded and overwhelmed with more events than can be processed. It is like finding the needle in the proverbial haystack, where the needle is abnormal behavior and the haystack all online communications. To be secure, every instance of abnormal behavior should be checked as it may represent botnet activity or similar threats.

Despite these challenges, with the proper resources, data can also be our greatest ally. Thanks to modern technology -- namely big data -- organizations can proactively look for outlier behavior and investigate and obtain the necessary threat intelligence to evaluate and mitigate security risks before further damage is done.

One such example of the successful use of Big Data involves the takedown of a well-known botnet. In February, Europol, along with Microsoft, Symantec, and AnubisNetworks, led the takedown operation of Ramnit. In this case, the massive haystack consisted of the communications generated between a global network of compromised machines and respective command and control servers, or C2s. C2s are centralized machines that are able to send commands and receive outputs of machines -- part of a botnet encrypted with multiple security layers to protect “the needle,” meaning the criminals behind the whole operation. Breaking and sinkholing the Ramnit botnet required patience and perseverance to understand how the botnet operated, how it was structured, and how it communicated with the C2.

The takedown
Before moving in, law enforcement needed intelligence on the botnet, namely its geographic dispersion and an understanding of the malware to identify communication protocols and C2 infrastructure mapping.

It took months to collect, aggregate, and analyze the Ramnit botnet data, which led to sinkholing the C2 infrastructure and delivering critical information to allow law enforcement to take over the C2s and arrest the criminals.

In the end, the takedown was a success and law enforcement took control of the C2 infrastructure. By accessing and analyzing threat data from a variety of sources, the takedown effectively minimized the presence of Ramnit and reduce botnet activity on the international scale with infected machines decreasing from over 3.2 million to less than 250,000 in the days following the operation.


A couple of months after the operation, we’ve seen an increase in Ramnit botnet activity, but it’s marginal when compared to the days prior to the takedown. This emergence of new activity highlights the importance of vigilance and constant monitoring of these types of threats as in many cases it can be like cutting the head off a Hydra.

While the average organization won’t find itself involved in a high stakes botnet takedown, there are a few key takeaways from the Ramnit takedown that can be applied to any security program:

  • Many organizations rely solely on inside data about possible security breaches. If for some reason internal systems have been compromised, there is a very high probability those systems aren’t doing a very good job, so it’s important to have added visibility over network traffic related to the organization -- like a fresh set of eyes or a sanity check, if you prefer, to ensure everything is ok.

  • Knowing that your organization has been compromised is the first step towards solving the threat, but in order to be effective it’s also necessary to have a rich and unique context about it. You need to know and understand who the enemy is and how it can the successful tackled.

  • At the end of the day, humans are the weakest link in the cybersecurity equation, so education, awareness, and the implementation of good practices are critical in keeping your organization and customers safe. 

Unfortunately, botnets don’t simply die, they are built to be resilient and survive even if the masterminds behind them are in prison. We can weaken them, but often they reemerge with a similar modus operandi and a new name. Organizations need to embrace an adaptive approach to security, understand the new threat actors, and the risks they may represent.

About the Author

Francisco Fonseca

CEO & Co-founder of AnubisNetworks

Francisco Fonseca is the co-founder and CEO of AnubisNetworks, a BitSight subsidiary. Francisco has 15 over 15 years experience in the telecommunication industry implementing and managing email platforms for corporate and ISP environments. He previously founded Crashless, and worked at Vodafone Portugal. He is also Vice President of the National Association of Young Business People and has taught at Moderna and Nova Universities.

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