Update (May 9): OSIRT had the opportunity to review the infected web app code for one of the compromised sites and has a great write-up to explain what was happening from a server-side vantage point.
Today, Zscaler identified yet another mass website compromise, this one impacting a number of popular media sites, including two radio stations in Washington, DC - Federal News Radio and WTOP. It's not clear if all of the sites impacted were leveraging a common backend platform that may have led to the compromise.
Sadly, mass compromises are now the norm. Attacks targeting end users generally involve some form of social engineering whereby the potential victim must be convinced to visit a site, download a file, etc. Attackers will therefore write a script designed to comb the web looking for popular sites exposing a common flaw and when identified, inject a single line of malicious code into the sites. In that way, any user visiting the otherwise legitimate (but now infected) site, can become a victim. This particular threat also displays another common trait - being dynamic in nature and only delivering content if the victim browser exhibits certain attributes. In this case, the injected content is only displayed when the browser's User Agent string reveals that Internet Explorer (IE) is being used. When IE is used to view one of the infected pages, the following code is sent to the browser:
|Deobfuscated version of the injected code
Once redirected to the malicious URLs, Fake AntiVirus scams and the ZeroAccess Trojan are delivered to the victim. MD5s for malware delivered include the following:
2e1997982c4dde48a995df5061f1438f 2b150bd07bb74426d676d8cb47451fd0 62547040ac637b63c2d531e17438597a 8858050e303cca778e5083ed4e442763 eee9941e4d01b65061f4fb621b2d708d b43c1d19d35e3606a7b6227cef561986
Thus far, Zscaler has identified the following compromised sites:
- WTOP Radio (Washington, DC) - wtop.com
- Federal News Radio (Washington, DC) - federalnewsradio.com
- The Christian Post - christianpost.com
- Real Clear Science - realclearscience.com
- Real Clear Policy - realclearpolicy.com
At the time of posting, these compromised sites were still offering up malicious content.