AOL halts malicious ads served by its advertising platform

The malicious ads had been served since late October, according to security company Cyphort said Tuesday it has stopped malicious advertisements being served by its advertising platforms after being alerted by a security company.

Cyphort, which specializes in detecting malware, found on Dec. 31 malicious ads being served on the U.S. and Canadian versions of the news site Huffington Post.

The malicious advertisements redirected users to other websites that attacked their computers and tried to install malware, according to a blog post from Cyphort.

Nick Bilogorskiy, [cq] Cyphort's director of security research, said was notified on Saturday and the attacks stopped on Monday. Cyphort's logs showed the attacks started in late October.

An spokesman confirmed Cyphort's findings via email and said the company took the necessary steps to fix the problem.

"AOL is committed to bringing new levels of transparency to the advertising process, ensuring ads uphold quality standards and create positive consumer experiences," the spokesman wrote.

A number of other sites were also affected, including, and, Cyphort wrote.

Malicious advertisements are a powerful way for hackers to compromise large numbers of computers. The ads are rigged to redirect users to other malicious Web pages.

The malicious ads shown by AOL redirected users to a Web page that hosted an exploit kit, the term for code that looks for software vulnerabilities on a user's computer that can be exploited to install malware.

Cyphort wrote that the exploit kit used was either NeutrinoEK or the Sweet Orange Kit. The kit served up an exploit for Adobe Systems' Flash program, a common target for hackers due to the voluminous number of vulnerabilities found in it.

Before landing on the attack site, users were bounced through a number of other websites, some of which used HTTPS encrypted connections in order to hide the servers used for the attack. Cyphort wrote that one of the HTTPS redirectors that was used was hosted on a Google App Engine page, which made analysis of the redirect harder because the traffic is encrypted.

The sites hosting the exploit kit were ".pl" domains, the country code top-level domain for Poland. Cyphort noticed that "" and "" -- both ad platforms owned by AOL -- were delivering ads that redirected users to the malicious domains.

Advertising platforms try to prevent malicious activity by vetting ads before they are shown. But there are a variety of tricks employed to skirt around the checks.

Bilogorskiy said attackers will submit ads to an advertising platform but wait a few days before enabling the malicious payload until after the ad has been approved. Sometimes, malicious ads will only attack every 10th user, making one more difficult to detect and remove.

"The ad networks get millions of ads submitted to them, and any one of them could be malvertising," he said. Advertising platforms "try to detect and filter malicious ads from their systems, but it is challenging."

"The potential damage is high, as ad networks have a very deep reach and can infect many people quickly," he said.

Send news tips and comments to Follow me on Twitter: @jeremy_kirk

Join the CSO newsletter!

Error: Please check your email address.


More about Adobe SystemsAOLGoogleOrange

Show Comments

Featured Whitepapers

Editor's Recommendations

Solution Centres

Stories by Jeremy Kirk

Latest Videos

  • 150x50

    CSO Webinar: The Human Factor - Your people are your biggest security weakness

    ​Speakers: David Lacey, Researcher and former CISO Royal Mail David Turner - Global Risk Management Expert Mark Guntrip - Group Manager, Email Protection, Proofpoint

    Play Video

  • 150x50

    CSO Webinar: Current ransomware defences are failing – but machine learning can drive a more proactive solution

    Speakers • Ty Miller, Director, Threat Intelligence • Mark Gregory, Leader, Network Engineering Research Group, RMIT • Jeff Lanza, Retired FBI Agent (USA) • Andy Solterbeck, VP Asia Pacific, Cylance • David Braue, CSO MC/Moderator What to expect: ​Hear from industry experts on the local and global ransomware threat landscape. Explore a new approach to dealing with ransomware using machine-learning techniques and by thinking about the problem in a fundamentally different way. Apply techniques for gathering insight into ransomware behaviour and find out what elements must go into a truly effective ransomware defence. Get a first-hand look at how ransomware actually works in practice, and how machine-learning techniques can pick up on its activities long before your employees do.

    Play Video

  • 150x50

    CSO Webinar: Get real about metadata to avoid a false sense of security

    Speakers: • Anthony Caruana – CSO MC and moderator • Ian Farquhar, Worldwide Virtual Security Team Lead, Gigamon • John Lindsay, Former CTO, iiNet • Skeeve Stevens, Futurist, Future Sumo • David Vaile - Vice chair of APF, Co-Convenor of the Cyberspace Law And Policy Community, UNSW Law Faculty This webinar covers: - A 101 on metadata - what it is and how to use it - Insight into a typical attack, what happens and what we would find when looking into the metadata - How to collect metadata, use this to detect attacks and get greater insight into how you can use this to protect your organisation - Learn how much raw data and metadata to retain and how long for - Get a reality check on how you're using your metadata and if this is enough to secure your organisation

    Play Video

  • 150x50

    CSO Webinar: How banking trojans work and how you can stop them

    CSO Webinar: How banking trojans work and how you can stop them Featuring: • John Baird, Director of Global Technology Production, Deutsche Bank • Samantha Macleod, GM Cyber Security, ME Bank • Sherrod DeGrippo, Director of Emerging Threats, Proofpoint (USA)

    Play Video

  • 150x50

    IDG Live Webinar:The right collaboration strategy will help your business take flight

    Speakers - Mike Harris, Engineering Services Manager, Jetstar - Christopher Johnson, IT Director APAC, 20th Century Fox - Brent Maxwell, Director of Information Systems, THE ICONIC - IDG MC/Moderator Anthony Caruana

    Play Video

More videos

Blog Posts