New Click-Fraud Attack Is Stealthiest Yet

An anonymous reader sends news from The Washington Post's Security Fix blog of a new Trojan horse program that takes click fraud to the next level. The Trojan, dubbed FFsearcher by SecureWorks, was among the pieces of malware installed by sites hacked with the Nine-Ball mass compromise, which attacked some 40,000 Web sites this month. The Trojan takes advantage of Google's "AdSense for Search" API, which allows Web sites to embed Google search results alongside the usual Google AdSense ads. (SecureWorks' writeup indicates that Yahoo search is targeted too, but the researchers saw no evidence if the malware redirecting Yahoo searches.) While most search hijackers give themselves away on the victim's machine by redirecting the browser through some no-name search engine, FFsearcher "...converts every search a victim makes through Google.com, so that each query is invisibly redirected through the attackers' own Web sites, via Google's Custom Search API. Meanwhile, the Trojan manipulates the victim's PC and browser so that the victim never actually sees the attacker-controlled Web site that is hijacking the search, but instead sees the search results as though they were returned directly from Google.com (and with Google.com in the victim browser's address bar, not the address of the attacker controlled site). Adding to the stealth is the fact that search results themselves aren't altered by the attackers, who are merely going after the referral payments should victims click on any of the displayed ads. What's more, the attackers aren't diverting clicks or ad revenue away from advertisers or publishers, as in traditional click fraud: They are simply forcing Google to pay commissions that it wouldn't otherwise have to pay." If FFSearcher were the only piece of malware on the machine, it would have a better chance of staying under the radar.

Comments

Re:How the server gets infected?

[Seth Kriticos]

Reading the article helps - there is only one server: my-web-way.com , which is supposedly controlled by the attackers. The whois entry reveals, that it is registered in Moskow, Russia.. probably with a fake name.

Now to what gets infected: Windows machines. It plays with DLL's and the Registry (described in the article).

Interesting is: this peace of mallware does not directly (perceivably) damage the user of the infected machine, but it generates revenue through (semi fake) Google ad clicks. I wonder how they (Google) will react.. would guess that big corporations get quite pissed by this kind of stuff. Let's wait and see..

Read The Fine Summary

[nacturation]

Why would they waste their time? Surely there are easier ways to steal from adsense that don't involve putting people at risk...

Were you just trying for first post, or did you have a point to make? "Why would they [the FFSearcher developers] waste their time?" Because it makes them money and, thus, is not a waste of time at all but rather quite the profitable use of their time. And from the summary, it sounds like FFSearcher does nothing malicious except for redirecting traffic such that it gets referral payments. How is that putting people at risk? And what are these easier-to-steal-from-adsense methods you're referring to?

Re:The flaw in their foolproof plan

[michaelhood]

Yeah, good thing no one clicks on Google's ads.

Google reported $21,128,514,000.00 in ad revenues for FY2008.

Re:Does this affect all browsers?

[Jahava]

The virus itself is a complicated one. As per the article, it was installed on the system during a mass exploit dubbed Nine-Ball, which was loaded onto 40,000 legitimate websites. Visiting those sites caused the Nine-Ball script to execute, which redirected an iframe to a page containing malicious code which mounts a series of attacks. Those mentioned by the site are:

• Exploit MS06-014, which targets the MDAC ActiveX control
• Exploit CVE-2006-5820, which targets the AOL SuperBuddy ActiveX control
• [Some] targeting Acrobat Reader"
• [Some targeting] QuickTime

So basically, an application (browser) visits this malicious page. If that application runs the ActiveX controls mentioned (and presumably Acrobat Reader and/or QuickTime), it was vulnerable to the initial Nine-Ball exploit. IE qualifies for all 4 of those; Firefox can use ActiveX (I believe, with a plugin), but not out of the box... however, it does have plugins for Acrobat Reader and QuickTime.

If any of those vulnerabilities were present with the applicaton visited the iframe, it runs malicious code that installs a crapton of viruses on the host computer, among them the FFSearcher virus.

Once FFSearcher is on your computer, it causes itself to get run all of the time, probably as Administrator. It then proceeds to:

1. Executes a Windows root-kit to hide its presence
2. Injects code into browser application processes; for IE, it will inject an IE-specific payload, and for Firefox, it will inject a Firefox-specific payload. Each payload causes the infected browser to do all the malicious redirecting that is described in lower-level detail in the article.

So a nice, clean, and secure IE / Firefox get started up, but Windows, itself infected, loads the virus into them! No vulnerabilities are exploited, here. Since FFSearcher runs as Administrator, everything it does is straightforward and allowed by the system; it can do basically anything. What it chooses to do is target IE and Firefox. Since it's running as Administrator, it doesn't have to exploit any vulnerabilities in either; it just barges in and rewrites parts of them to do its bidding. Administrator can do things like that.

In conclusion, there isn't any vulnerability in IE or Firefox that's involved in FFSearcher, and the only reason FFSearcher doesn't pwn other browsers is because the author didn't bother to write a payload for them, too. FFSearcher, itself, was installed due to some browser vulnerability that happened sometime, and now, permanently present on the system, takes advantage of its Administrator privileges to do some pretty wicked stuff.