Feeds

Guessing at compromised host numbers

The fine art of pulling numbers from your nether regions

Security for virtualized datacentres

After much waiting by end users, and a lot of hoping from interested Information Security watchers, Microsoft has finally added detection for the Storm Trojan (Nuwar, Zhelatin, etc) to its Malicious Software Removal Tool. The most recent update, released on September 11th, included detection for this malicious software, and the early results are not quite what most people were expecting.

With various claims being made that there are millions upon millions of compromised hosts that make up the available network that the botnet controllers have access to, it would be assumed that the Microsoft Malicious Software Removal Tool should be removing a large number of affected systems from the Internet.

That isn't quite what Microsoft found. In a post to its TechNet blog, Microsoft's Anti-Malware team discovered that the total number of Storm Trojan removals placed it third in the overall list of malware variants removed from the systems of end users. With more than 660,000 removals each, Renos and Zlob malware types led the Nuwar / Storm family of malware. Nuwar variants, and components of Nuwar were successfully removed from just under a quarter of a million systems.

A third party researcher notified Microsoft of a drop of almost 20% of the total DoS capability for the malware bot network in the days following the update to the MSRT, implying that it was directly related to the update. While correlation does not imply causation, it is an interesting data point that could point to an infection rate significantly lower than most have predicted. Microsoft's own assessment is that the quarter of a million machines cleaned up represented almost 100,000 machines in the active botnet. Combined with the 20% reduction, it suggests that the overall size of the botnet is only 500,000 machines, with another couple of hundred thousand that are not active, but are infected.

There is no doubt that the Nuwar menace is something that is causing a lot of users significant trouble. What is being called into doubt is the total spread of infected systems. It is possible that Microsoft have not successfully identified infected variants of Nuwar, and it is possible that most infected systems are not running any form of malware removal tool (either through ignorance, hubris, or just not being aware of them). It may also be that many infected systems have already been cleaned by third party antimalware software, though this should have been evident in an overall reduction of botnet operation.

This article originally appeared at Sûnnet Beskerming

© 2007 Sûnnet Beskerming Pty. Ltd

Sûnnet Beskerming is an independent Information Security firm operating from the antipodes. Specialising in the gap between threat emergence and vendor response, Sûnnet Beskerming provides global reach with a local touch.

Secure remote control for conventional and virtual desktops

More from The Register

next story
NASTY SSL 3.0 vuln to be revealed soon – sources (Update: It's POODLE)
So nasty no one's even whispering until patch is out
Russian hackers exploit 'Sandworm' bug 'to spy on NATO, EU PCs'
Fix imminent from Microsoft for Vista, Server 2008, other stuff
'LulzSec leader Aush0k' found to be naughty boy not worthy of jail
15 months home detention leaves egg on feds' faces as they grab for more power
Forget passwords, let's use SELFIES, says Obama's cyber tsar
Michael Daniel wants to kill passwords dead
FBI boss: We don't want a backdoor, we want the front door to phones
Claims it's what the Founding Fathers would have wanted – catching killers and pedos
Kill off SSL 3.0 NOW: HTTPS savaged by vicious POODLE
Pull it out ASAP, it is SWISS CHEESE
Facebook slurps 'paste sites' for STOLEN passwords, sprinkles on hash and salt
Zuck's ad empire DOESN'T see details in plain text. Phew!
prev story

Whitepapers

Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
Win a year’s supply of chocolate
There is no techie angle to this competition so we're not going to pretend there is, but everyone loves chocolate so who cares.
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?
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.