Feeds

Thousands of WordPress sites commandeered by Black Hole

Webmasters, update TimThumb now!

Security for virtualized datacentres

Mass attacks that exploit a known vulnerability in the WordPress publishing platform have continued to bear fruit for hackers, with thousands of websites claimed in the past few weeks, a researcher said.

The security bug, in a widely used image resizing utility known as TimThumb, allows attackers to seize control of WordPress websites, one of the victims warned nine weeks ago. A few days later, a security researcher found almost 4,400 WordPress sites had been commandeered in an attack that poisoned Google Image results with sites that attempted to trick users into installing counterfeit antivirus software. He speculated the cause was the same TimThumb exploit.

Although a fix for the TimThumb vulnerability has been available for more than two months, plenty of websites remain vulnerable. According to a research report published by Avast on Monday, thousands of websites have been infected by Black Hole, a hack-by-numbers toolkit available in underground forums for about $1,500 or for free for a scaled-down version. The kit installs an iframe in infected sites that silently redirects visitors to malicious sites.

"The bad guys are using a security vulnerability in non-updated TimThumb," Avast researcher Jan Sirmer wrote. "This allows attackers to upload and execute arbitrary PHP code in the TimThumb cache directory which will download other malicious files."

Avast alone blocked the redirection attempts from 3,500 unique websites in August and 2,515 sites last month, and Sirmer said he expects to see similar results this month. That may be only a small percentage of the total number of infected sites, since Avast is used by a small minority of people browsing the web. Sirmer said attackers may have compromised some of the websites by exploiting weak passwords.

Once a site is infected, it's not always easy to remove all the malicious code. Denis Sinegubko, the Russian researcher who discovered the WordPress attack used to poison Google Image results, has advised webmasters of compromised sites to look for rogue rules in the .htaccess files in the site root and above the site root directory. He has more here. ®

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.