Equifax, TransUnion Hit by Malicious JavaScript Security Risk

Tracking code for website performance data on an Equifax site allegedly had been injected with code that downloaded a fake Flash downloader onto user's systems.

On Oct.12, security researcher Randy Abrams first publicly posted that he had found a new Equifax risk that was exploiting users. The immediate concern was that Equifax had potentially been breached, yet again.

As it turns out, the vulnerability was not the result of a new breach at Equifax, but rather the result of third party JavaScript code used for website performance tracking. The same issue also allegedly impacted Equifax's rival TransUnion, according to security firm MalwareBytes.

"Despite early media reports,  Equifax can confirm that its systems were not compromised and that the reported issue did not affect our consumer online dispute portal," Equifax stated in an email sent to eWEEK.

Equifax has been under intense public scrutiny since it first publicly disclosed on Sept. 7 that it was the victim of a data breach that exposed personally identifiable information on 145.5 million American consumers. With the Oct.12 report of a potential security risk on the Equifax customer portal, the company was quick to respond and determine the root cause.

"The issue involves a third-party vendor that Equifax uses to collect website performance data, and that vendor's code running on an Equifax website was serving malicious content," Equifax stated. "Since we learned of the issue, the vendor's code was removed from the webpage and we have taken the webpage offline to conduct further analysis."

It's unclear how long the infected third party JavaScript code was present on the Equifax site or how many customers may have potentially been impacted. Abrams found the security issue as he was attempting to access a page on the Equifax customer portal.

"As I tried to find my credit report on the Equifax website I clicked on an Equifax link and was redirected to a malicious URL," Abrams blogged. "The URL brought up one of the ubiquitous fake Flash Player Update screens."

The fake Flash Player in fact is a form of adware that identified as Adware.Eorezo and often uses the filename MediaDownloaderIron.exe. According to antivirus engine analysis platform VirusTotal, only 3 out of 65 different antivirus technologies actually are able to identify Adware.Eorezo as a form of malware.

The malware was injected in a file identified as "fireclick.js" which was also being used by Equifax's rival credit reporting agency TransUnion.

"A quick search for other websites that were using it (fireclick.js) returned—surprisingly—another consumer reporting credit agency, namely TransUnion and their Central America website," MalwareBytes security researcher Jerome Segura blogged. Like Equifax, TransUnion has removed the offending page and is now conducting an investigation.

Sean Michael Kerner is a senior editor at eWEEK and InternetNews.com. Follow him on Twitter @TechJournalist.

Sean Michael Kerner

Sean Michael Kerner

Sean Michael Kerner is an Internet consultant, strategist, and contributor to several leading IT business web sites.