Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.


07:10 AM
Connect Directly

Researchers Name Top Six Spamming Botnets

Marshal researchers say six botnets are sending 85% of the world's spam

Researchers with Marshal’s TRACE team have identified six botnets that together are currently responsible for distributing 85 percent of all spam, Dark Reading has learned. And the results might surprise you.

Of the six top-spamming botnets Marshal will reveal next week -- Srizbi, Rustock, Mega-D, Hacktool.spammer, Pushdo, and Storm -- the infamous Mega-D and Storm are low on the totem pole. Srizbi is leading the pack, sending 40 percent of spam; Rustock, 21 percent; Mega-D, 9 percent; Hacktool.spammer, 8 percent; Pushdo, 6 percent; and Storm, only about 2 percent.

Marshal earlier this month publicly pegged Mega-D as the king of spam, spewing about 32 percent of the world’s spam and by far overtaking Storm, according to the security firm. Storm was sending about 2 percent then as well, after peaking somewhere around 20 percent in September, Marshal says.

Mega-D -- best known by its male sexual enhancement pill promotions under the names Herbal King, Express Herbals, and VPXL -- later suddenly shut down its botnet after attracting the attention of Marshal and SecureWorks, which analyzed its command and control infrastructure. (See MayDay! Sneakier, More Powerful Botnet on the Loose.)

“That spooked them and they shut down,” says Michael Whitehurst, vice president of global support for Marshal. “But this past weekend, Mega-D fired things up and started spamming again.”

Whitehurst says that even when Mega-D went offline, the male-enhancement spam stayed alive. “The expectation was that the whole Express Herbals/enhancement spam would die out. But it didn’t,” he says. “What we saw was that volume shifted to other botnets. We saw four of the other major spam bots sending it -- Pushdo, Hacktool.spammer, Rustock, and Srzbi. It makes you wonder about the relationship between all of them.”

Marshal, which is identifying some of these botnets by their bot malware names, says there is another 15 percent of malware being sent by botnets that they have not yet pinpointed.

And it turns out botnet size doesn’t matter when it comes to spam distribution. “The size of a botnet isn't necessarily equivalent to the amount of spam it’s generating,” Whitehurst says. “Two weeks ago, the 35,000-bot Mega-D was sending more spam than the 85,000-bot Storm.” (See The World's Biggest Botnets .)

Then there’s the MayDay botnet that Damballa has been closely watching, which can evade leading antivirus products and so far has compromised thousands of hosts, with about 96.5 percent of the infected machines in the U.S., and about 2.5 percent in Canada. Damballa considers MayDay a potential successor to Storm, even though it’s nowhere near as large.

Marshal’s Whitehurst says it’s unclear whether having more bots is actually a handicap in spamming because it's tougher to remain inconspicuous, or whether it’s a matter of which botnet is generating more business for the spammer. “I think we’re one of first groups analyzing what these botnets are producing and how much they are producing, and how that accounts for spam in the world,” he says.

Have a comment on this story? Please click "Discuss" below. If you'd like to contact Dark Reading's editors directly, send us a message.

  • Marshal Inc.
  • SecureWorks Inc.
  • Damballa Inc.

    Kelly Jackson Higgins is the Executive Editor of Dark Reading. She is an award-winning veteran technology and business journalist with more than two decades of experience in reporting and editing for various publications, including Network Computing, Secure Enterprise ... View Full Bio

    Comment  | 
    Print  | 
    More Insights
  • Comments
    Newest First  |  Oldest First  |  Threaded View
    COVID-19: Latest Security News & Commentary
    Dark Reading Staff 10/23/2020
    7 Tips for Choosing Security Metrics That Matter
    Ericka Chickowski, Contributing Writer,  10/19/2020
    Russian Military Officers Unmasked, Indicted for High-Profile Cyberattack Campaigns
    Kelly Jackson Higgins, Executive Editor at Dark Reading,  10/19/2020
    Register for Dark Reading Newsletters
    White Papers
    Current Issue
    Special Report: Computing's New Normal
    This special report examines how IT security organizations have adapted to the "new normal" of computing and what the long-term effects will be. Read it and get a unique set of perspectives on issues ranging from new threats & vulnerabilities as a result of remote working to how enterprise security strategy will be affected long term.
    Flash Poll
    How IT Security Organizations are Attacking the Cybersecurity Problem
    How IT Security Organizations are Attacking the Cybersecurity Problem
    The COVID-19 pandemic turned the world -- and enterprise computing -- on end. Here's a look at how cybersecurity teams are retrenching their defense strategies, rebuilding their teams, and selecting new technologies to stop the oncoming rise of online attacks.
    Twitter Feed
    Dark Reading - Bug Report
    Bug Report
    Enterprise Vulnerabilities
    From DHS/US-CERT's National Vulnerability Database
    PUBLISHED: 2020-10-23
    A Cross-Site Request Forgery (CSRF) vulnerability is identified in FruityWifi through 2.4. Due to a lack of CSRF protection in page_config_adv.php, an unauthenticated attacker can lure the victim to visit his website by social engineering or another attack vector. Due to this issue, an unauthenticat...
    PUBLISHED: 2020-10-23
    FruityWifi through 2.4 has an unsafe Sudo configuration [(ALL : ALL) NOPASSWD: ALL]. This allows an attacker to perform a system-level (root) local privilege escalation, allowing an attacker to gain complete persistent access to the local system.
    PUBLISHED: 2020-10-23
    NVIDIA GeForce Experience, all versions prior to, contains a vulnerability in the ShadowPlay component which may lead to local privilege escalation, code execution, denial of service or information disclosure.
    PUBLISHED: 2020-10-23
    An arbitrary command execution vulnerability exists in the fopen() function of file writes of UCMS v1.4.8, where an attacker can gain access to the server.
    PUBLISHED: 2020-10-23
    NVIDIA GeForce Experience, all versions prior to, contains a vulnerability in NVIDIA Web Helper NodeJS Web Server in which an uncontrolled search path is used to load a node module, which may lead to code execution, denial of service, escalation of privileges, and information disclosure.