Feeds

Opera site served Blackhole malvertising, says antivirus firm

'No need to issue a press release', firm tells press

Protecting against web application threats using SSL

Opera has suspended ad-serving on its portal as a precaution while it investigates reports that surfers were being exposed to malware simply by visiting the Norwegian browser firm's home page.

Malicious scripts loaded by portal.opera.com were redirecting users towards a malicious site hosting the notorious BlackHole exploit kit, said a Romanian anti-virus firm BitDefender, which said it had detected the apparent attack on its automated systems. BitDefender said it promptly warned Opera after it detected the problem on Wednesday. It seems likely the scripts had been loaded through a third-party advertisement, a practice commonly known as malvertising.

Opera has yet to confirm the problem, but has disabled advertising scripts on its portal in case they are tainted. The browser firm says:

We are investigating the claim, and while we are working with this, we have taken some precautionary measures just to be safe, such as disabling the ads temporarily on portal.opera.com. We disabled ads yesterday [Wednesday], right after becoming aware of the claim, as a standard precaution and the ads had been disabled for several hours when Bitdefender issued a press release.

A blog post by BitDefender claimed that cybercrooks were using obfuscated script to hide the attack. The security firm said Opera fans had been exposed to attack simply by firing up the popular alternative browser software.

"The hidden and obfuscated piece of code in the Opera Portal homepage inserts an iFrame that loads malicious content from an external source," BitDefender explains. "If the Opera user hasn’t changed their default homepage, active malicious content is loaded from a third-party website whenever they open their browser."

In controlled tests, BitDefender researchers were served with a PDF-based exploit designed to infect an unlucky user with a freshly compiled variant of the infamous ZBot (ZeuS) banking Trojan. The exploit was served up from a (likely compromised) server in Russia, according to BitDefender. It's unclear how many people might have been exposed to this drive-by-download-style attack from Opera's portal, much less how many surfers might have been infected.

"We have no indications that anyone was infected before or after we disabled the ads yesterday [Wednesday]," an Opera spokesman told El Reg.

"Malvertising" incidents are far from rare. Previous victims have included Spotify, the London Stock Exchange, The Pirate Bay, ITV.com and Major League Baseball, among many others. Diagnosing and resolving tainted ad problems tends to be far trickier than cases where a web server itself is running malicious script, so Opera is wise to suspend ad-serving while it looks into the potential problem. ®

Reducing the cost and complexity of web vulnerability management

More from The Register

next story
Early result from Scots indyref vote? NAW, Jimmy - it's a SCAM
Anyone claiming to know before tomorrow is telling porkies
TOR users become FBI's No.1 hacking target after legal power grab
Be afeared, me hearties, these scoundrels be spying our signals
Home Depot: 56 million bank cards pwned by malware in our tills
That's about 50 per cent bigger than the Target tills mega-hack
Hackers pop Brazil newspaper to root home routers
Step One: try default passwords. Step Two: Repeat Step One until success
NORKS ban Wi-Fi and satellite internet at embassies
Crackdown on tardy diplomatic sysadmins providing accidental unfiltered internet access
UK.gov lobs another fistful of change at SME infosec nightmares
Senior Lib Dem in 'trying to be relevant' shocker. It's only taxpayers' money, after all
Critical Adobe Reader and Acrobat patches FINALLY make it out
Eight vulns healed, including XSS and DoS paths
Spies would need SUPER POWERS to tap undersea cables
Why mess with armoured 10kV cables when land-based, and legal, snoop tools are easier?
prev story

Whitepapers

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.
WIN a very cool portable ZX Spectrum
Win a one-off portable Spectrum built by legendary hardware hacker Ben Heck
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.
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?
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.