Rustock Botnet: Dead, or just dazed?

Microsoft--working with legal and technical partners--has taken down the Rustock botnet

The Rustock botnet--one of the most prolific sources of spam--has gone silent. Microsoft worked with security vendors and the civil court system to pull the plug on Rustock. Some security experts question, though, if the absence of Rustock will have a significant impact on spam volume, or whether we have truly heard the last of Rustock, or if it is just dormant for a while.

Rustock is the same botnet that recently went silent--apparently taking a break for the 2011 holiday season. A post on the Microsoft on the Issues blog describes how Microsoft used the lessons learned from squashing the Waledac botnet last year to apply a combination of legal and technical methods for taking down the more vast and complex Rustock botnet.

The Microsoft post explains, "Rustock's infrastructure was much more complicated than Waledac's, relying on hard-coded Internet Protocol addresses rather than domain names and peer-to peer command and control servers to control the botnet. To be confident that the bot could not be quickly shifted to new infrastructure, we sought and obtained a court order allowing us to work with the U.S. Marshals Service to physically capture evidence onsite and, in some cases, take the affected servers from hosting providers for analysis."

The confiscated servers helped Microsoft and its partners knock Rustock offline, and are also providing valuable forensic evidence for security experts to analyze to learn more about the intricate inner-workings of the botnet infrastructure.

Symantec confirms that traffic from the Rustock botnet ceased as of 11:30am Eastern time on Wednesday, March 16. However, Symantec isn't confident that the absence of Rustock will have a significant impact on the volume of spam being spewed.

A Symantec spokesperson commented that, although Rustock has been a dominant source of spam--accounting for nearly half of all spam in 2010, it is too early to tell if killing Rustock has much effect. "In the last few months, other botnets have increased their output to match--or even exceed--that of Rustock. As a result, the takedown of this major botnet hasn't had much noticeable effect on the overall amount of spam and email traffic patterns appear normal.

AppRiver's Troy Gill is not so sure we have heard the last of Rustock. Gill notes that AppRiver did see a drop in spam levels as the Rustock command and control servers were disrupted, but adds "Interestingly, we have seen general, overall spam levels creep back to their previous levels in the past few hours. Although it is too early to tell for sure, this disruption appears to be temporary, similar to the 10-day disruption of Rustock back in November of 2010."

Whether it is permanent, or Rustock has the resilience to bounce back, Microsoft's ongoing efforts to combat this botnet and others--working with a team of legal and technical partners--is welcome, and it should be congratulated.

Join the CSO newsletter!

Error: Please check your email address.

Tags spamantispamMicrosoftvirusessecurityphishingmalware

More about MicrosoftSymantec

Show Comments

Featured Whitepapers

Editor's Recommendations

Solution Centres

Stories by Tony Bradley

Latest Videos

  • 150x50

    CSO Webinar: Will your data protection strategy be enough when disaster strikes?

    Speakers: - Paul O’Connor, Engagement leader - Performance Audit Group, Victorian Auditor-General’s Office (VAGO) - Nigel Phair, Managing Director, Centre for Internet Safety - Joshua Stenhouse, Technical Evangelist, Zerto - Anthony Caruana, CSO MC & Moderator

    Play Video

  • 150x50

    CSO Webinar: The Human Factor - Your people are your biggest security weakness

    ​Speakers: David Lacey, Researcher and former CISO Royal Mail David Turner - Global Risk Management Expert Mark Guntrip - Group Manager, Email Protection, Proofpoint

    Play Video

  • 150x50

    CSO Webinar: Current ransomware defences are failing – but machine learning can drive a more proactive solution

    Speakers • Ty Miller, Director, Threat Intelligence • Mark Gregory, Leader, Network Engineering Research Group, RMIT • Jeff Lanza, Retired FBI Agent (USA) • Andy Solterbeck, VP Asia Pacific, Cylance • David Braue, CSO MC/Moderator What to expect: ​Hear from industry experts on the local and global ransomware threat landscape. Explore a new approach to dealing with ransomware using machine-learning techniques and by thinking about the problem in a fundamentally different way. Apply techniques for gathering insight into ransomware behaviour and find out what elements must go into a truly effective ransomware defence. Get a first-hand look at how ransomware actually works in practice, and how machine-learning techniques can pick up on its activities long before your employees do.

    Play Video

  • 150x50

    CSO Webinar: Get real about metadata to avoid a false sense of security

    Speakers: • Anthony Caruana – CSO MC and moderator • Ian Farquhar, Worldwide Virtual Security Team Lead, Gigamon • John Lindsay, Former CTO, iiNet • Skeeve Stevens, Futurist, Future Sumo • David Vaile - Vice chair of APF, Co-Convenor of the Cyberspace Law And Policy Community, UNSW Law Faculty This webinar covers: - A 101 on metadata - what it is and how to use it - Insight into a typical attack, what happens and what we would find when looking into the metadata - How to collect metadata, use this to detect attacks and get greater insight into how you can use this to protect your organisation - Learn how much raw data and metadata to retain and how long for - Get a reality check on how you're using your metadata and if this is enough to secure your organisation

    Play Video

  • 150x50

    CSO Webinar: How banking trojans work and how you can stop them

    CSO Webinar: How banking trojans work and how you can stop them Featuring: • John Baird, Director of Global Technology Production, Deutsche Bank • Samantha Macleod, GM Cyber Security, ME Bank • Sherrod DeGrippo, Director of Emerging Threats, Proofpoint (USA)

    Play Video

More videos

Blog Posts

Market Place