Botnets Still a Major Threat, Researchers Say at RSA


levels may have dropped, but botnets are still busy.

In fact, security researchers at this year’s RSA

Conference highlighted a mix of botnets both famous and unheard of that are

growing on the strength of do-it-yourself

kits and pay-per-install (PPI) systems.

Joe Stewart, director of malware research for Dell SecureWorks, reported

that the most prolific spam botnet today is Rustock, which he estimates has

250,000 bots in its army. While in the past Rustock has periodically been

overtaken by other botnets, it has pulled away because of the author’s

continued development to the botnet’s codebase. Among its tactics: not mapping

hostnames associated with the Rustock HTTP communication directly to the IP

address of a Rustock controller, and having Rustock control servers run a TOR

exit node to avoid disconnection by network administrators.

“It has probably the most thought and development, stealth, obfuscation

[and] evasion built in to what it’s doing, and it’s evolved these things over

the past few years,” he said.

But while Rustock has the name and the fame, there are other botnets many

people may not have heard of that have sneakily built up armies of bots by

piggybacking on the growth of other malware. An example of this can be found

with Lethic, which Stewart estimates has 75,000 bots. Lethic has been seen

lately being installed by another bot known as “Butterfly” or “Bfbot.”

Bfbot botnets have been seen installing other spam Trojans as well, making the

specific Bfbot system part of a growing ecosystem of pay-per-install


For more, read the eWeek article: RSA Conference: Researchers Go Inside the Botnet Threat.

CIO Insight Staff
CIO Insight Staff
CIO Insight offers thought leadership and best practices in the IT security and management industry while providing expert recommendations on software solutions for IT leaders. It is the trusted resource for security professionals who need network monitoring technology and solutions to maintain regulatory compliance for their teams and organizations.

Get the Free Newsletter!

Subscribe to Daily Tech Insider for top news, trends, and analysis.

Latest Articles