Web attack that poisons Google results gets worse

The Gumblar attack has infected more than 3000 Web sites

A new attack that peppers Google search results with malicious links is spreading quickly, the U.S. Computer Emergence Response Team warned on Monday.

The attack, which has intensified in recent days, can be found on several thousand legitimate Web sites, according to security experts. It targets known flaws in Adobe's software and uses them to install a malicious program on victims' machines, CERT said.

The program then steals FTP login credentials from victims and uses that information to spread further. It also hijacks the victim's browser, replacing Google search results with links chosen by the attackers.

Security experts started tracking the attack in March, when it had infected several hundred Web sites, but in recent weeks the number of infected sites has jumped dramatically. The attack has been called Gumblar because at one point it used the Gumblar.cn domain, though on Monday it had switched to a different one.

Security vendor ScanSafe has counted more than 3,000 infected Web sites, up from around 800 just over a week ago.

That kind of continued growth is unusual, according to Mary Landesman, a senior security researcher with ScanSafe. Attackers have launched many widespread Web attacks over the past few years, but after a few months the total number of infected sites usually drops as Webmasters clean up their servers.

With Gumblar, more and more sites are now being infected. Landesman believes it's because Gumblar's creators have been good at obfuscating their attack code and making it harder to spot on infected sites. And because they've been stealing FTP login credentials, they've been able to use a few new tricks to get their software onto the sites. "They're doing things like changing folder permissions ... and leaving behind multiple ways that they can get back into the server," she said.

Still, Web attacks have become so widespread that Gumblar remains a relatively small-scale phenomenon, according to Symantec Security Response Product Manager John Harrison. Last year, Symantec counted 18 million online attacks against its customers. With Gumblar, it has counted 10,000. "It's really just another day with drive-by downloads," he said. "There really are so many of these."

Security experts say that if you're using a fully-patched system with up-to-date security software, you should be protected from these attacks. To date, they've worked by hitting the victim with malicious PDF or Flash files.

Join the Good Gear Guide newsletter!

Error: Please check your email address.

Tags Googlesecurity

Our Back to Business guide highlights the best products for you to boost your productivity at home, on the road, at the office, or in the classroom.

Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Robert McMillan

IDG News Service
Show Comments

Most Popular Reviews

Latest News Articles

Resources

PCW Evaluation Team

Azadeh Williams

HP OfficeJet Pro 8730

A smarter way to print for busy small business owners, combining speedy printing with scanning and copying, making it easier to produce high quality documents and images at a touch of a button.

Andrew Grant

HP OfficeJet Pro 8730

I've had a multifunction printer in the office going on 10 years now. It was a neat bit of kit back in the day -- print, copy, scan, fax -- when printing over WiFi felt a bit like magic. It’s seen better days though and an upgrade’s well overdue. This HP OfficeJet Pro 8730 looks like it ticks all the same boxes: print, copy, scan, and fax. (Really? Does anyone fax anything any more? I guess it's good to know the facility’s there, just in case.) Printing over WiFi is more-or- less standard these days.

Ed Dawson

HP OfficeJet Pro 8730

As a freelance writer who is always on the go, I like my technology to be both efficient and effective so I can do my job well. The HP OfficeJet Pro 8730 Inkjet Printer ticks all the boxes in terms of form factor, performance and user interface.

Michael Hargreaves

Windows 10 for Business / Dell XPS 13

I’d happily recommend this touchscreen laptop and Windows 10 as a great way to get serious work done at a desk or on the road.

Aysha Strobbe

Windows 10 / HP Spectre x360

Ultimately, I think the Windows 10 environment is excellent for me as it caters for so many different uses. The inclusion of the Xbox app is also great for when you need some downtime too!

Mark Escubio

Windows 10 / Lenovo Yoga 910

For me, the Xbox Play Anywhere is a great new feature as it allows you to play your current Xbox games with higher resolutions and better graphics without forking out extra cash for another copy. Although available titles are still scarce, but I’m sure it will grow in time.

Featured Content

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?