Feeds

Malware lingers months on infected PCs

Resident evil

Using blade systems to cut costs and sharpen efficiencies

Malware stays around on infected PCs far longer than previously thought, according to the latest research from Trend Micro.

Previous estimates suggested that a compromised machine remains infected for approximately six weeks. Based on an analysis of around 100 million compromised IPs, Trend Micro concludes that many infected IPs are infected (or repeatedly infected) for more than two years, with a median infection length of 300 days. Four in five compromised machines are infected for more than a month.

A graph from Trend Micro suggests that if systems aren't disinfected quickly then infection tends to linger around indefinitely, possibly until the point users exchange compromised boxes for new machines.

Trend's study also looked at the botnet landscape. Three strains of botnet agent - Koobface, Zeus/Zbot and Ilomo/Clampi - are causing the most damage in terms of identity theft.

The Koobface botnet, for example, has co-opted around 51,000 machines into its ranks. Koobface uses between five and six command and control centers (C&C) to control these zombie clients at any one time. If a particular control domain is taken down by a particular provider, then botnet herders behind the malware establishes a new command outpost elsewhere. Between the middle of March and mid-August 2009, Trend Micro recorded around 46 Koobface control domains.

Trend's stats don't cover dormant infections by the Conficker worm. Stats from the Anti-Conficker Working Group suggest the malware is still resident on more than five million compromised machines. ®

Boost IT visibility and business value

More from The Register

next story
14 antivirus apps found to have security problems
Vendors just don't care, says researcher, after finding basic boo-boos in security software
Secure microkernel that uses maths to be 'bug free' goes open source
Hacker-repelling, drone-protecting code will soon be yours to tweak as you see fit
Only '3% of web servers in top corps' fully fixed after Heartbleed snafu
Just slapping a patched OpenSSL on a machine ain't going to cut it, we're told
How long is too long to wait for a security fix?
Synology finally patches OpenSSL bugs in Trevor's NAS
Israel's Iron Dome missile tech stolen by Chinese hackers
Corporate raiders Comment Crew fingered for attacks
Roll out the welcome mat to hackers and crackers
Security chap pens guide to bug bounty programs that won't fail like Yahoo!'s
HIDDEN packet sniffer spy tech in MILLIONS of iPhones, iPads – expert
Don't panic though – Apple's backdoor is not wide open to all, guru tells us
Researcher sat on critical IE bugs for THREE YEARS
VUPEN waited for Pwn2Own cash while IE's sandbox leaked
prev story

Whitepapers

Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
Application security programs and practises
Follow a few strategies and your organization can gain the full benefits of open source and the cloud without compromising the security of your applications.
How modern custom applications can spur business growth
Learn how to create, deploy and manage custom applications without consuming or expanding the need for scarce, expensive IT resources.
Securing Web Applications Made Simple and Scalable
Learn how automated security testing can provide a simple and scalable way to protect your web applications.