Feeds

Attackers hone Twitterific exploit-site concealer

Conquer hacktile dysfunction

Beginner's guide to SSL certificates

Malware writers have revamped code that uses a popular Twitter command to generate hard-to-predict domain names, a technique that brings stealth to their drive-by exploits.

Four weeks ago, when The Register reported Twitter application programming interfaces were being used to generate pseudorandom domain names, none of the addresses checked had actually been registered. Denis Sinegubko, the Russian researcher who discovered the technique, speculates the creators abandoned it because it was buggy and required too much effort.

Now, Sinegubko has identified a new version of the algorithm that refines the process. What's more, at least some of the names are now being registered and the sites are being used to push malware.

"The new incarnation of this attack uses new algorithm and it is active right now," he told El Reg on Wednesday.

The technique gives the exploit writers a limitless list of of fly-by-night domain names to cycle through in an attempt to complicate the job of white hat hackers trying to thwart the attack. Rather than there being a single address to block or disconnect, the site hosting the malware changes every 12 hours.

The domain names are generated by an algorithm that looks at the top topics being discussed on Twitter at particular times. Because the trending topics, as they're known, can't be predicted in advance, the method prevents white hats from being able to snap up the addresses weeks or months in advance, as researchers combating the Conficker worm have done.

The technique was discovered by analyzing thousands of legitimate websites that had been compromised so they redirected visitors to malicious servers. Sinegubko identified the algorithm by reverse engineering highly obfuscated javascript that was injected into the compromised websites. As the addresses of the sites hosting the malware change, so too do the iframes on the compromised sites.

Sinegubko has created a tool to predict what the next domain will be. There's about a 24-hour lag between the time his script generates the domain name and the time it will be used (assuming the prediction is correct) to host the malware. That gives admins plenty of leeway to block the sites before they become active. It also presents fleet-footed white hats with the opportunity to register domain names ahead of the bad guys.

"I've been testing this tool for about three days now," he said. "So far it is correct."

You can watch the pseudorandom generator in action here (although you'll need to allow javascript to run). Sinegubko's writeup of the new generator is here. ®

Choosing a cloud hosting partner with confidence

More from The Register

next story
SMASH the Bash bug! Apple and Red Hat scramble for patch batches
'Applying multiple security updates is extremely difficult'
Apple's new iPhone 6 vulnerable to last year's TouchID fingerprint hack
But unsophisticated thieves need not attempt this trick
Hackers thrash Bash Shellshock bug: World races to cover hole
Update your gear now to avoid early attacks hitting the web
Oracle SHELLSHOCKER - data titan lists unpatchables
Database kingpin lists 32 products that can't be patched (yet) as GNU fixes second vuln
Who.is does the Harlem Shake
Blame it on LOLing XSS terroristas
Researchers tell black hats: 'YOU'RE SOOO PREDICTABLE'
Want to register that domain? We're way ahead of you.
Stunned by Shellshock Bash bug? Patch all you can – or be punished
UK data watchdog rolls up its sleeves, polishes truncheon
Ello? ello? ello?: Facebook challenger in DDoS KNOCKOUT
Gets back up again after half an hour though
prev story

Whitepapers

Providing a secure and efficient Helpdesk
A single remote control platform for user support is be key to providing an efficient helpdesk. Retain full control over the way in which screen and keystroke data is transmitted.
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.
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.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.
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.