Feeds

Conficker call-backs threaten to swamp legit domains

Southwest Airlines faces Friday the 13th horror

Security for virtualized datacentres

The infamous Conficker worm is set to disrupt the operation of at least four legitimate websites this month.

Machines infected with Conficker (Downadup) are programmed to dial home for updates through a list of domains which changes every day. Microsoft is heading an alliance to block unregistered domains on this list but that still leaves a number of registered domains on the storm front.

An analysis by Sophos identified that of 7750 Conficker call-home domains found around half are active (ie resolve to an IP address). Fortunately the vast majority of these (3,861 from 3,889) domains resolve to only 42 unique IP addresses. That leaves 28 domains to worry about, most of which are up for sale with registrars.

That still leaves four frequently-visited legitimate domains which will, for one day at least, be left on the speed-dial list of infected machines. Jogli.com (Big Web Great Music) is due for a call up on 8 March, followed by wnsux.com (which is run as a secondary domain by Southwest Airlines) on the 13 March, qhflh.com (Women's Net in Qinghai Province, China) five days later and praat.org on the 31 March.

Instead of facing a near-invulnerable homicidal nutter in a hockey mask, Southwest Airlines website faces a zombie onslaught this Friday the 13th.

"A legitimate domain that happens to make it into the Conficker call-home list is a problem for two reasons," explained Mike Wood of SophosLabs, Canada. "First, without proper investigation, they may end up on a blocklist and prevent users from accessing their services.

"Second, those millions of Conficker infected machines contacting the domain on its given day may overload the site and essentially result in a denial-of-service attack."

The websites affected stand to be swamped with requests for updates from infected machines on the relevant days. In the worse case scenario, that means online check-ins with Southwest Airlines on Friday, 13 March might become impossible.

Sophos suggests either suspending the affected domains, and using an alternative domain, or filtering the HTTP query that Conficker uses, as techniques to avoid a possible denial of service attack. Filtering HTTP requests is a heavy lifting job, and technically tricky. Sophos has contacted the sites on the hitlist who face real problems, with the sole upside being that they have some notice of the imminent blow. ®

Secure remote control for conventional and virtual desktops

More from The Register

next story
Russian hackers exploit 'Sandworm' bug 'to spy on NATO, EU PCs'
Fix imminent from Microsoft for Vista, Server 2008, other stuff
Microsoft pulls another dodgy patch
Redmond makes a hash of hashing add-on
FYI: OS X Yosemite's Spotlight tells Apple EVERYTHING you're looking for
It's on by default – didn't you read the small print?
'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
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.