Feeds

Security firm chokes sprawling spam botnet

Mega-D no more

Protecting against web application threats using SSL

A botnet that was once responsible for an estimated third of the world's spam has been knocked out of commission thanks to researchers from security firm FireEye.

After carefully analyzing the machinations of the massive botnet, alternately known as Mega-D and Ozdok, the FireEye employees last week launched a coordinated blitz on dozens of its command and control channels. The channels were used to send new spamming instructions to the legions of zombie machines that make up the network.

Almost immediately, the spam stopped, according to M86 Security blog. Last year, the email security firm estimated the botnet was the leading source of spam until some of its servers were disabled.

The body blow is good news to ISPs that are forced to choke on the torrent of spam sent out by the pesky botnet. But because many email servers already deployed blacklists that filtered emails sent from IP addresses known to be used by Ozdok, end users may not notice much of a change, said Jamie Tomasello, an abuse operations manager at antispam firm Cloudmark.

The takedown effort is significant because it shows that a relatively small company can defeat a for-profit network that took extraordinary measures to ensure it remained operational. Not only did Ozdok reserve a long list of domain names as command and control channels, it also used hard-coded DNS servers. When all else failed, its software was able to dynamically generate new domain names on the fly.

With head chopped off of Ozdok, more than 264,000 IP addresses were found reporting to sinkholes under FireEye's control, an indication of the massive number of zombies believed to have belonged to the botnet. FireEye researchers plan to work with the ISPs to identify the owners of the orphaned bots so their owners can clean up the mess.

FireEye researchers said the key to dismantling the giant ring was a coordinated effort that worked in multiple directions all at once so that bot herders didn't have a chance to counteract. "As it turns out, no matter how many fallback mechanisms are in place, if they aren't all implemented properly, the botnet is vulnerable," they wrote. ®

Reducing the cost and complexity of web vulnerability management

More from The Register

next story
Spies would need SUPER POWERS to tap undersea cables
Why mess with armoured 10kV cables when land-based, and legal, snoop tools are easier?
Early result from Scots indyref vote? NAW, Jimmy - it's a SCAM
Anyone claiming to know before tomorrow is telling porkies
TOR users become FBI's No.1 hacking target after legal power grab
Be afeared, me hearties, these scoundrels be spying our signals
Jihadi terrorists DIDN'T encrypt their comms 'cos of Snowden leaks
Intel bods' analysis concludes 'no significant change' after whistle was blown
Home Depot: 56 million bank cards pwned by malware in our tills
That's about 50 per cent bigger than the Target tills mega-hack
Hackers pop Brazil newspaper to root home routers
Step One: try default passwords. Step Two: Repeat Step One until success
China hacked US Army transport orgs TWENTY TIMES in ONE YEAR
FBI et al knew of nine hacks - but didn't tell TRANSCOM
Microsoft to patch ASP.NET mess even if you don't
We know what's good for you, because we made the mess says Redmond
NORKS ban Wi-Fi and satellite internet at embassies
Crackdown on tardy diplomatic sysadmins providing accidental unfiltered internet access
prev story

Whitepapers

Secure remote control for conventional and virtual desktops
Balancing user privacy and privileged access, in accordance with compliance frameworks and legislation. Evaluating any potential remote control choice.
WIN a very cool portable ZX Spectrum
Win a one-off portable Spectrum built by legendary hardware hacker Ben Heck
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Beginner's guide to SSL certificates
De-mystify the technology involved and give you the information you need to make the best decision when considering your online security options.