Threat Research Blog

Malware With Your News? Forbes Website Victim of Malvertising Attack

September 22, 2015 | by J. Gomez, Genwei Jiang

From Sept. 8 to Sept. 15, 2015, the Forbes.com website was serving content from a third-party advertising service that had been manipulated to redirect viewers to the Neutrino and Angler exploit kits. We notified Forbes, who worked quickly to correct the issue.

This type of malicious redirection is known as malvertising, where ad networks and content publishers are abused and leveraged to serve ads that redirect users to malicious sites.

Neutrino Attack Chain

The attack starts when the following URL is requested from the Forbes.com website, as depicted in Figure 1:

hXXp://www3.forbes[.]com/test/[redacted]/IWC_ForbesLife_E-Reader_unit/fif.html

The following URLs were seen as referrers in the requests for fif.html:

www.forbes.com/2010/08/24/sabbatical-leave-work-leadership-careers-advice.html	www.forbes.com/sites/johnlamattina/2015/04/13/ should-the-fda-require-cv-outcome-studies-for-diabetes-drugs-before-approval/
www.forbes.com/search/?q=CSR+articles	www3.forbes.com/business/the-worlds-100- highest-paid-athletes/?utm_campaign=highest- paid-athletes-2015&utm_source=yahoo-gemini &utm_medium=referral
www.forbes.com/sites	www3.forbes.com/investing/the-grateful- graduates-index-2015-the-top-50-roi-colleges/? kwp_0=40495&utm_campaign=the-grateful- graduates-index-2015-the-top-50-roi-colleges& utm_source=FacebookTest1&utm_medium= referral&utm_content=3&kwp_4=231627& kwp_1=186159
www.forbes.com/sites/abrambrown/2012/10/29/what-can-close-the-nyse-world-war-presidential-funerals-and-hurricane-sandy/	www3.forbes.com/lists/the-richest- person-in-every-state/?utm_campaign=richest-by-state&utm_source=taboola& utm_medium=referral&utm_content=reuters-reuters

Table 1. Referrers leading to request for “/test/[redacted]/IWC_ForbesLife_E-Reader_unit/fif.html”

Figure 1. Request to forbes.com; parameters contain URLs for loading ad content

Visible in the parameter, “&lu=” is the encoded URI for a .js file from the host s.flite[.]com (see Figure 2). flite[.]com is another ad platform.

Figure 2. Request to s.flite[.]com

Loading the .js file results in the following iframe being loaded (Figures 3 and 4):

Figure 3. iframe to eminetwork[.]com

Figure 4. Request to eminetwork[.]com

The file FDPU_08_17_15_New_Eng_Educ_Innov contains another injected iframe leading to the Neutrino exploit kit (Figure 5).

Figure 5. iframe to Neutrino exploit kit

This results in loading of the Neutrino landing page that sets up the exploitation stage (Figure 6, as follows):

Figure 6. Neutrino landing page w/ reference to Flash exploit

The exploit page downloads a flash exploit (MD5 e8ce10aab2c0585df10fe9420278e25c) (Figure 7).

Figure 7. Flash exploit being downloaded

The flash contains a set of exploits (shown in Figure 8) in the binaryData, and leverages one of them based on the victim’s environment to download the malware. The binaryData is encoded using RC4; if the exploit is targeting IE, it will be further encoded using zlib inflate method.

binaryData	Decrypted md5	Summary
1.bin	fd9d3a5f51053818e38a79ad63292add	Flash, cve-2015-5119
2.bin	71b488c677490a82e8a9060a6a34bb9a	Flash, cve-2015-5122
3.bin	abf2c18c6a68e8a70eb069ae7cc4593d	Angler EK's IE cve-2015-2419 exploit
4.bin	575ba6a43945a739583633badee50f7f	IE, cve-2013-2551
5.bin	41edea8d4e6d187eb0f977b8bec27a98	Flash, cve-2014-0569
6.bin	adf2e242611449c8e93f3d849ec6a1cc	Vbscript, cve-2014-6332
7.bin	0266f91ffde4f00c233c7089dc38162b	Vbscript, cve-2014-6332

Figure 8. Exploits embedded

ADDITIONAL INFORMATION

Further research showed that this malvertising attack led not only to the Neutrino exploit kit, but to the Angler exploit kit, as well. This switching between exploit kits behavior is not new and has been recently documented here.

The following table lists some of the Angler URLs and the respective referrers. Note that all referrers come from the eminetwork.com domain.

Angler URL

REFERRER

Angler URL

REFERRER

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