Teaching old worms new tricks

March 2009 Cyber Security

Win32.Worm.Downadup uses new tricks to spread itself without being easily detected.

Win32.Worm.Downadup, a worm which spreads by exploiting a vulnerability in the Windows RPC Server Service, has been detected by BitDefender. The Downloadup worm (also called Conficker or Kido) is nothing new. It made its first appearance late November 2008, exploiting the MS08-067 vulnerability to spread unhindered in local area networks. Its purpose was to install rogue security software on infected computers.

In late December, BitDefender Labs uncovered a new version of the worm called Win32.Worm.Downadup.B. The malware comes with a list of new features, aside from the present spreading routine, which has also shown signs of improvement.

The worm now uses USB sticks to spread. By copying itself in a random folder created inside the RECYCLER directory, used by the Recycle Bin to store deleted files, and creating an autorun.inf file in the root folder of the infected drive, the worm automatically executes if the infected computer’s Autorun feature is enabled.

The worm also patched certain TCP functions to block access to security-related websites by filtering every address that contains certain strings. This makes it harder to remove since information about it is nearly impossible to gather from an infected computer. Additionally, it removes all access rights of the user, except execute and directory usage, to protect its files.

The worm is also built to avoid antivirus detection by working with rarely used APIs in order to circumvent virtualisation technologies. It disables Windows updates and certain network traffic, optimising Vista features to ease its spreading.

Win32.Worm.Downadup.B comes with a domain name generation algorithm similar to the one found in botnets like Rustock. It composes 250 domains every day and checks some of them for updates or other files to download and install.

Having a state-of-the-art update system, a good protection scheme and many people that do not patch their systems, this worm has great potential to become a rival to already established botnets like Storm or Srizbi.

For more technical details please visit the Malwarecity Blog at: http://www.malwarecity.com/blog.html and the BitDefender description: http://www.bitdefender.com/VIRUS-1000462-en--Win32.Worm.Downadup.Gen.html

Facebook users, beware of the fake hubs!

BitDefender researchers have detected an IM-based spam wave automatically sent to accounts which promises a hot date if the Facebook’s users access the typosquatted link.

Users should pay extremely close attention to details, such as Websites names and avoid following links received in e-mail or IM spam. Failing to do so might result in stolen log-in credentials. Phishers could exploit them to harvest e-mail addresses, retrieve other contact details stored in accounts or post spam messages or malware disguised behind banner advertising.





Share this article:
Share via emailShare via LinkedInPrint this page



Further reading:

SecurityHQ to enhance crucial security operations in southern Africa
Cyber Security
SecurityHQ helpsbusinesses detect,respond to and mitigate the growing number of cyber threats targeting the region.

Read more...
Managed cybersecurity for every business
J2 Software Cyber Security
J2 is a cybersecurity-focused technology group founded in 2006, serving over 200 customers on three continents.

Read more...
Services to get things done
J2 Software Cyber Security
The world has seen exponentialgrowth in cybercrimes. Syndicatesand individuals have turned to ourhyper-connected world to profitfrom our shortcomings.

Read more...
Saving MSPs’ time and money
Cyber Security
New research from Acronis dives into critical issues facing MSPs, including cybersecurity attacks, vendor sprawl, remote work, lack of trust and managing SaaS tools.

Read more...
Three common schemes of business email compromise
Cyber Security
Between May and July 2021, Kaspersky products prevented more than 9500 BEC attacks globally, including those against businesses in air transportation, industry, retail, IT and delivery.

Read more...
A back to basics layered approach
Cyber Security
Cybercrime has risen exponentially since the start of the global pandemic. While no security is foolproof, crafting a security posture with multiple layers, built on the basic tenets of cybersecurity is certainly a good start.

Read more...
Security monitoring of user behaviour
Cyber Security
SaaS Alerts has released the capability for managed service providers to monitor the user behaviour associated with their instances of IT Glue, the IT documentation platform for MSPs.

Read more...
Prevention is better than cure
Cyber Security
Ransomware incidents ‘exploded’ in June 2020, which saw twice as many ransomware attacks as the month prior, taking advantage of remote workers being away from the help of IT teams.

Read more...
Cloud vulnerabilities: what CISOs need to consider
Cyber Security
With the digital transformation and an acceleration of modern technology, there has been a vast increase in security issues that chief information security officers (CISOs) have had to face.

Read more...
A ransomware crisis plan is now a business imperative
Arcserve Southern Africa Cyber Security
The digital era has ushered in a period of massive disruption, enabled by connection and access to information like we’ve never seen before.

Read more...