Krebs on Security

Toward A Greater Mobile Mal-Awareness

July 24, 2013

Several recent developments in mobile malware are conspiring to raise the threat level for Android users, making it easier for attackers to convert legitimate applications into malicious apps and to undermine the technology that security experts use to tell the difference.

Source: Symantec

Last week, Symantec warned about a new malware toolkit or “binder” designed to Trojanize legitimate Android apps with a backdoor that lets miscreants access infected mobile devices remotely. Binders have been around in a variety of flavors for many years, but they typically are used to backdoor Microsoft Windows applications.

Symantec notes that the point-and-click Androrat APK Binder is being used in conjunction with an open-source remote access Trojan for Android devices called called AndroRAT. “Like other RATs, it allows a remote attacker to control the infected device using a user friendly control panel,” Symantec’s Andrea Lelli wrote. “For example, when running on a device, AndroRAT can monitor and make phone calls and SMS messages, get the device’s GPS coordinates, activate and use the camera and microphone and access files stored on the device.”

The company said while it has detected only a few hundred AndroRAT infections worldwide, but that it expects that number increase as more tools for AndroRAT like the APK binder emerge.

Perhaps more worryingly, Symantec said this week that it had discovered two malicious Android apps in the wild that take advantage of a newly discovered and potentially quite serious security hole in Android applications. As first outlined roughly two weeks ago by researchers at BlueBox Security, the so-called “Master Key” vulnerability could let attackers convert almost any Android application into a Trojan, all without altering its cryptographic digital signature. Android uses these signatures to determine if an app is legitimate and to verify that an app hasn’t been tampered with or modified.

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One-Stop Bot Chop-Shops

July 23, 2013

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New fraudster-friendly content management systems are making it more likely than ever that crooks who manage botnets and other large groupings of hacked PCs will extract and sell all credentials of value that can be harvested from the compromised machines.

Templates like this are helping to spread one-stop-fraud shops.

I’ve often observed that botmasters routinely fail to fully eat what they kill. That is, they tend to chronically undervalue the computers at their disposal, and instead focus on extracting specific resources from hacked PCs, such as using them as spam relays or harvesting online banking credentials. Meanwhile, other assets on the hacked PC that have street value go unused and “wasted” from the fraudster’s perspective.

More often, when miscreants do seek to extract and monetize all of the account credentials from their hacked PCs, they do so by selling access to their raw botnet “logs” — huge text files that document the notable daily activities of the botted systems. To borrow from another food metaphor, this is the digital equivalent of small farms selling their fruits and vegetables as “pick-your-own;” such commerce produces some added revenue without requiring much more work on the seller’s part.

Recently, I’ve been spotting more online fraud shops set up using what appear to be pre-set templates that can be used to sell all manner of credentials from hacked PCs. These shops all sell credit and debit card information, of course, but also lists of emails culled from victim computers, hacked VPN and RDP credentials, Cpanel installations, PHP mailers, FTP access, SSH logins, and online gambling accounts. Some of the panels are even reselling hacked credentials at popular porn sites. Goods can be purchased via virtual currencies such as Perfect Money and bitcoin.

The shop shown below — blackhatstore[dot]ru — borrows the trademarked image of the Black Hat security conference franchise. It’s sometimes said that there’s no such thing as bad press, but I’m pretty sure the folks at Black Hat don’t want their brand advertised or associated in this way (by the way, I’ll be speaking at this year’s Black Hat in Las Vegas next week). I alerted the Black Hat organizers to this fraudulent site, so I wouldn’t expect it to remain live much longer.

This bot chop shop trades on the good name and trademarks of the Black Hat security conference franchise owned by UBM Tech.

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Styx Crypt Makers Push DDoS, Anti-Antivirus Services

July 19, 2013

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I recently published a piece that examined the role of several Ukrainian men likely responsible for making and marketing the Styx Pack malware exploit kit. Today’s post will show how this same enterprise is linked to a DDoS protection scheme and a sprawling cybercrook-friendly malware scanning service that is bundled with Styx-Crypt.

Anonymous antivirus scanning service — captain-checker.com — bundled with Styx.

As I noted in a graphic accompanying a July 8 analysis of Styx, the $3,000 exploit pack includes a built-in antivirus scanning service that employs at least 17 antivirus products. The scanning service is “anonymous,” in that it alerts Styx customers whenever one of the antivirus tool detects their malware as such, but the service also prevents the antivirus products from reporting home about the new malware detections.

When Styx customers click on one of these malware scanning reports from within the Styx pack panel itself, the full scanning results are displayed in a new browser window at the domain captain-checker[dot]com (see screenshot above). The Styx panel that I examined earlier this month was based at the Internet address 5.199.167.196, and was reachable only by appending the port number 10665 to the numeric address. At first, I thought this might be a standard port used by Styx installations but that turns out not to be the case, according to interviews with other researchers. I didn’t realize it at the time, but now I’m thinking it’s likely that the panel I examined was actually one run by the Styx Pack curators themselves.

I discovered that although captain-checker[dot]com is hosted at another address (46.21.146.130), it also had this 10665 port open. I noticed then that captain-checker shares that server with 12 other Web sites. All of those sites also respond on port 10665, each revealing a captain-checker login page. Among the 12 is uptimer[dot]biz, one of two sites that led to the identity of Alexander “Nazar” Nazarenko — one of the main marketers and sellers of Styx pack.

Not only are all of these sites on the same server, an Nmap scan of these systems shows that they all are on the same Windows workgroup — “Reality7.” This dovetails nicely with the other domain that I noted in that July 10 story as tied to Nazarenko — reality7solutions[dot]com.

Many of the other domains on the server (see graphic to the left) use some variation of the word “wizard,” and share a Google Analytics code, UA-19307857. According to SameID.net, this code is embedded in the homepage for at least 38 different Web sites.

In my previous story on Nazarenko and his Styx Pack business partner — Max “Ikar” Gavryuk — I noted that both men were advertising “Reality Guard,” a service to help protect clients from distributed denial-of-service (DDoS) attacks designed to knock sites offline. I had a closer look at their site — reality-guard[dot]com — and learned several interesting things: For starters, the site also responds with a captain-checker[dot]com login page when you append “:10665” to the domain name. It also is on a Microsoft Windows workgroup called “Reality7”. Finally, the reality-guard[dot]com home page includes an icon for virtual currency Webmoney that when hovered over pops up Nazar’s Webmoney account (someone changed the name on this account from “Nazar” to “Lives” within hours after my July 10 story on the Styx Pack purveyors).

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Botcoin: Bitcoin Mining by Botnet

July 18, 2013

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An increasing number of malware samples in the wild are using host systems to secretly mine bitcoins. In this post, I’ll look at an affiliate program that pays people for the mass installation of programs that turns host machines into bitcoin mining bots.

The FeodalCash bitcoin mining affiliate program.

Bitcoin is a decentralized, virtual currency, and bitcoins are created by large numbers of CPU-intensive cryptographic calculations. As Wikipedia explains, the processing of Bitcoin transactions is secured by servers called bitcoin miners. These servers communicate over an internet-based network and confirm transactions by adding them to a ledger which is updated and archived periodically using peer-to-peer filesharing technology. In addition to archiving transactions, each new ledger update creates some newly minted bitcoins.

Earlier this week, I learned of a Russian-language affiliate program called FeodalCash which pays its members to distribute a bitcoin mining bot that forces host PCs to process bitcoin transactions (hat tip to security researcher Xylitol). FeodalCash opened its doors in May 2013, and has been recruiting new members who can demonstrate that they have control over enough Internet traffic to guarantee at least several hundred installs of the bitcoin mining malware each day.

The FeodalCash administrator claims his mining program isn’t malware, although he cautions all affiliates against submitting the installer program to multi-antivirus scanners such as Virustotal; sending the program that installs bitcoin mining bot to Virustotal “greatly complicates the work with antivirus” on host PCs. Translation: Because services like Virustotal share information about new malware samples with all participating antivirus vendors, scanning the installer will make it more likely that antivirus products on host PCs will flag the program as malicious. Rather, the administrator urged users who want to check the files for antivirus detection to use a criminal friendly service like scan4u[dot]net or chk4me[dot]com, which likewise scan submitted files with dozens of different antivirus tools but block those tools from reporting home about new and unidentified malware variants.

This Google-translated version of the site shows the builder for the installer.

I gained access to an affiliate account and was able to grab a copy of the mining program. I promptly submitted the file to Virustotal and found it was flagged as a trojan horse program by at least two antivirus products. This analysis at automated malware scanning site malwr.com shows that the mining program installer ads a Windows registry key so that the miner starts each time Windows boots up. It also indicates that the program beacons out to pastebin.com (perhaps to deposit a note about each new installation).

The FeodalCash administrator also claims that his affiliates are not permitted to distribute the installer file in any way that violates the law, but of course it’s unclear which national laws he might be talking about. At the same time, the affiliate program’s Web site includes a graphical tool that helps affiliates create a custom installer program that can install silently and be disguised with a variety of program icons that are similar to familiar Windows icons.

Also, the administrator demands that new users demonstrate the ability to garner hundreds to thousands of installs per day. This is a rather high install rate, and it appears many if not all affiliates are installing the mining program by bundling it with other executable programs distributed by so-called pay-per-install (PPI) programs. This was apparent because a source managed to gain administrative-level access to the back-end database for the FeodalCash program, which includes hundreds of messages between affiliates and the administrator; most of those messages are from new registrants sending the administrator screenshots of their traffic and installs statistics at various PPI affiliate programs.

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Getting Skimpy With ATM Skimmers

July 16, 2013

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Cybercrooks can be notoriously cheap, considering how much they typically get for nothing. I’m reminded of this when I occasionally stumble upon underground forum members trying to sell a used ATM skimmer: Very often, the sales thread devolves into a flame war over whether the fully-assembled ATM skimmer is really worth more than the sum of its parts.

Card skimmer device made for Wincor/Nixdorf ATMs

Such was the fate of an audio-based ATM skimmer put up for sale recently on a private crime forum. The seller, a Ukrainian, was trying to offload a relatively pro-grade skimmer powered by parts cannibalized from an MP3 player and a small spy camera. The seller set the price at $2,450, but made the mistake of describing the device’s various parts, all of which can be purchased inexpensively from a variety of online retailers.

For example, he told forum members that the main component in the card skimmer as an MSR-605, which is a handheld magnetic stripe reader of the sort that you might find attached to a cash register/point-of-sale machine at a retail clothing store, for example.

This ubiquitous device can be had for approximately $200 at a number of places online, including Newegg.com and Amazon.com. The seller went on to describe the inexpensive flash storage drive that was incorporated in his device, and the modified tiny video camera that was hidden on the underside of a fake fascia designed to be affixed to the top of the ATM and record victims entering their PINs.

This tiny spy camera powers the fake ATM fascia that records victims entering their PINs.

The image below shows the fake fascia as it appears from the side meant to be pointed toward the PIN pad.

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DEF CON To Feds: We Need Some Time Apart

July 10, 2013

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One of the more time-honored traditions at DEF CON — the massive hacker convention held each year in Las Vegas — is “Spot-the-Fed,” a playful and mostly harmless contest to out undercover government agents who attend the show.

But that game might be a bit tougher when the conference rolls around again next month: In an apparent reaction to recent revelations about far-reaching U.S. government surveillance programs, DEF CON organizers are asking feds to just stay away.

In a brief blog post published this evening at the DEF CON Web site titled, “Feds, We Need Some Time Apart,” DEF CON owner and hacker-in-chief Jeff Moss (a.k.a. “The Dark Tangent”) suggested it was probably in the best interests of the feds to make themselves scarce at this year’s con.

“For over two decades DEF CON has been an open nexus of hacker culture, a place where seasoned pros, hackers, academics, and feds can meet, share ideas and party on neutral territory. Our community operates in the spirit of openness, verified trust, and mutual respect.

When it comes to sharing and socializing with feds, recent revelations have made many in the community uncomfortable about this relationship. Therefore, I think it would be best for everyone involved if the feds call a ‘time-out’ and not attend DEF CON this year.

This will give everybody time to think about how we got here, and what comes next.”

It’s been a while since DEF CON was a place where feds really had to watch their backs. I didn’t have the privilege to attend the first DEF CON 21 years ago, but it’s safe to say that relations between the hacker community and the feds were for many years colored by a sense of mutual antagonism and mistrust.

Much of that attitude seemed to have changed in the wake of 9/11, and for the past decade the relationship between the two camps has thawed and even warmed quite a bit. Intelligence and law enforcement agencies have come to find the conference a reliably fertile and lucrative grounds for recruiting talent. Heck, things had improved so much by this time last year that the conference’s keynote was given by none other than Keith Alexander, the director of the National Security Agency.

Now with the NSA in the hot seat over allegations of broad and intrusive electronic eavesdropping programs directed at U.S. citizens and our allies abroad, it remains to be seen whether officials from the NSA, CIA or other three-letter agencies will make any strong or sustained showing at this year’s gathering. But in any case, this announcement from DEF CON should serve as a fair warning to feds who do decide to stick around past Black Hat, a more corporate and fed-heavy conference that directly precedes DefCon: Spot-the-Fed could well turn into a hack-the-fed competition.

Who’s Behind The Styx-Crypt Exploit Pack?

July 10, 2013

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Earlier this week I wrote about the Styx Pack, an extremely sophisticated and increasingly popular crimeware kit that is being sold to help miscreants booby-trap compromised Web sites with malware. Today, I’ll be following a trail of breadcrumbs that leads back to central Ukraine and to a trio of friends who appear to be responsible for marketing (if not also making) this crimeware-as-a-service.

As I noted in Monday’s story, what’s remarkable about Styx is that while most exploit kits are sold on private and semi-private underground forums, Styx has been marketed and sold via a regular Web site: styx-crypt[dot]com. The peddlers of this service took down their site just hours after my story ran, but versions of the site cached by archive.org hold some important clues about who’s responsible for selling this product.

At the bottom of the archived styx-crypt homepage, we can see two clickable banners for an account at virtual currency Webmoney to which potential customers of Styx will need to send money in order to purchase a license for the software. The Webmoney account #268711559579 belongs to a Webmoney Purse number Z268711559579. Follow that link and you’ll see that the registered username attached to that purse is “Ikar.” If we look closer we can see that Ikar’s Webmoney purse is connected to another purse at Webmoney account 317426476957, which is this purse belonging to a user named “Nazar.” (Update: July 11, 10:14 p.m.: Both Ikar and Nazar changed the names on their Webmoney accounts after this story ran. Thankfully, archive.org cached the old data. The links to the purses above have been changed accordingly.)

Both Ikar and Nazar are nicknames that were used in Styx sales threads on several underground forums, including damagelab[dot]org, secnull[dot]cc and antichat[dot]ru. In these threads, Ikar used the contact address “ikar@core.im“, while Nazar listed “nazar@hush.ai“. Both addresses are associated with forum accounts named “Ikar” and “Renzor” (for examples, see this cached, Google-Translated page from Renzor’s account on antichat.ru, and this cached page from secnull[dot]cc). Nazar’s address is linked to a “Max Lighter” profile on Facebook, but not much more information is available on that profile.

reality7solutions.com

Ikar@core.im doesn’t appear to be connected to anything special, but Nazar’s address was used as the point-of-contact in registering two very interesting domains: reality7solutions.com and uptimer.biz. Looking at the familiar wormhole-like squiggly at the top of reality7solutions.com, I noticed it was very similar to the rotating icon (youtube.com video) used by the Styx pack.

Reality7solutions.com’s homepage lists an address in the United States for a company called EPAM Systems, which according to the business directory maintained by Hoovers is a public company that specializes in IT outsourcing. Hoovers says the company provides “software development and other IT services to US and European customers primarily from development centers in Russia, Belarus, Hungary, Ukraine, Kazakhstan and Poland.”

The ICQ number listed on the homepage of reality7solutions.com belongs to a Website design professional from Khmelnitsky, Ukraine named Stanislav Shangin. If we look at Schangin’s personal page where he lists all of the Web sites he’s been hired to create, we can see he designed both styx-crypt[dot]com and reality7solutions.com, among dozens of other sites. Shangin did not respond to requests for comment.

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Adobe, Microsoft Release Critical Updates

July 9, 2013

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Patch Tuesday is upon us once again. Adobe today pushed out security fixes for its Flash and Shockwave media players. Separately, Microsoft released seven patch bundles addressing at least 34 vulnerabilities in Microsoft Windows and other software. At least one of the Windows flaws is already being exploited in active attacks.

Six of the seven Microsoft patches released today earned the company’s most dire “critical” rating, meaning the patches plug security holes that could be exploited by malware or miscreants with no help from PC users, save for visiting a hacked site or opening a specially crafted document.

Microsoft and security experts are calling special attention to MS13-053, which fixes at least eight flaws in Windows’ implementation of TrueType font files. These critical TrueType vulnerabilities exist on nearly every supported version of Windows, including XP, Vista, Windows 7 and Windows 8, and can be exploited to gain complete control over a vulnerable Windows system, just by having the user visit a Web page that contains malicious TrueType content. To make matters worse, Microsoft says one component of this vulnerability (CVE-2013-3660) is already being exploited in the wild.

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Styx Exploit Pack: Domo Arigato, PC Roboto

July 8, 2013

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Not long ago, miscreants who wanted to buy an exploit kit — automated software that helps booby-trap hacked sites to deploy malicious code — had to be fairly well-connected, or at least have access to semi-private underground forums. These days, some exploit kit makers are brazenly advertising and offering their services out in the open, marketing their wares as browser vulnerability “stress-test platforms.”

Styx Pack victims, by browser and OS version.

Aptly named after the river in Greek mythology that separates mere mortals from the underworld, the Styx exploit pack is a high-end software package that is made for the underground but marketed and serviced at the public styx-crypt[dot]com. The purveyors of this malware-as-a-service also have made a 24 hour virtual help desk available to paying customers.

Styx customers might expect such niceties for the $3,000 price tag that accompanies this kit. A source with access to one Styx kit exploit panel that was apparently licensed by a team of bad guys shared a glimpse into their operations and the workings of this relatively slick crimeware offering.

The Styx panel I examined is set up for use by a dozen separate user accounts, each of which appears to be leveraging the pack to load malware components that target different moneymaking schemes. The account named “admin,” for example, is spreading an executable file that tries to install the Reveton ransomware.

Other user accounts appear to be targeting victims in specific countries. For example, the user accounts “IT” and “IT2” are pushing variants of the ZeuS banking trojan, and according to this Styx panel’s statistics page, Italy was by far the largest source of traffic to the malicious domains used by these two accounts. Additional apparently country-focused accounts included “NL,” AUSS,” and “Adultamer” (“amer” is a derisive Russian slur used to describe Americans).

ZeuS Trojan variants targeted at Italian victims were detected by fewer than 5 out 17 antivirus tools.

An exploit kit — also called an “exploit pack” (Styx is marketed as “Styx Pack”) is a software toolkit that gets injected into hacked or malicious sites, allowing the attacker to foist a kitchen sink full of browser exploits on visitors. Those visiting such sites with outdated browser plugins may have malware silently installed.

Unlike other kits, Styx doesn’t give a detailed breakdown of the exploits used in the panel. Rather, the panel I looked at referred to its bundled exploits by simple two-digit numbers. This particular Styx installation used just four browser exploits, all but one of which targets recent vulnerabilities in Java. The kit referred to each exploit merely by the numbers 11, 12, 13 and 32.

According to the considerable legwork done by Kafeine, a security blogger who digs deeply into exploit kit activity, Styx Kit exploit #11 is likely to be CVE-2013-1493, a critical flaw in a Java browser plugin that Java maker Oracle fixed with an emergency patch in March 2013. Exploit 12 is almost certainly CVE-2013-2423, another critical Java bug that Oracle patched in April 2013. In an instant message chat, Kafeine says exploit #13 is probably CVE-2013-0422, a critical Java vulnerability that was patched in January 2013. The final exploit used by the kit I examined, number 32, maps to CVE-2011-3402, the same Microsoft Windows font flaw exploited by the Duqu Trojan.

The Styx stats page reports that the hacked and malicious sites used by this kit have been able to infect roughly one out of every 10 users who visited the sites. This particular Styx installation was set up on June 24, 2013, and since that time it has infected approximately 13,300 Windows PCs — all via just those four vulnerabilities (but mostly the Java bugs).

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Carberp Code Leak Stokes Copycat Fears

June 27, 2013

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The source code for “Carberp” — a botnet creation kit coded by a team of at least two dozen hackers who used it to relieve banks of an estimated $250 million — has been posted online for anyone to download. The code leak offers security experts a fascinating and somewhat rare glimpse into the malcoding economy, but many also worry that its publication will spawn new hybrid strains of sophisticated banking malware.

Carberp admin panel. Source: Xylibox.blogspot.com

The leak appears to have begun, as these things often do, with the sale of the source code in a semi-private cybercrime forum. On June 5, a member of the Lampeduza crime forum said he was selling the Carberp source to a single buyer, with a starting price of $25,000. The seller said he was helping out one of the developers of the code, who was short on cash.

By mid-June, links to download the entire Carberp archive were being posted on multiple forums, as first documented by Trusteer. Since then, experts from around the world have been tearing through the two-gigabyte archive to learn more about the code and its potential for future abuse in new and existing malware creations.

“Leaking the source code was not like the leaking of a weapon, but more like the leaking of a tank factory,” wrote one Ukrainian tech blogger on Livejournal.

According to Peter Kruse, a specialist with the Copenhagen-based CSIS Security Group, the package includes the Carberp bootkit; this is a component that can subvert the Patchguard protection in Windows 7 x86 and 64-bit systems so that the malware loads itself at the most basic levels of the system (Kruse said the bootkit component is incomplete and does not work against Windows 8 PCs).

Also included are components of a Trojan known as UrSnif, as well as an extremely popular and prevalent rival botnet creation kit called Citadel.

“As with the leakage of the ZeuS source code, back in May 2011, this means that criminals have every chance to modify and even add new features to the kit,” Kruse wrote, noting that the Carberp archive also contains several text files that appear to be records of private chats and various usernames and passwords.

CHEEKY CODERS

Last year, Russian and Ukrainian authorities arrested a loosely-affiliated group of hackers accused of programming and using Carberp to rob millions from bank accounts of their countrymen. According to an account of the law enforcement action in the Russian news outlet Kommersant, Carberp was coded by a team of about 20-25 people under the age of 30. Most of the men had never met face-to-face. Each worked remotely and was responsible for developing specific modules of the Carberp code, components that were then transmitted to a main development server in Odessa, Ukraine.

Some of the leaked Carberp source code archives.

Members of the coding forum kernelmode.info have been poring over comments left in the code by the Carberp developers. One set of comments, translated from Russian by a KrebsOnSecurity reader, suggests the developer was frustrated by having to program within the confines of what he considered sloppy operating system or perhaps Web browser plugin code.

“I will rip off someone’s hands for this kind of code!” the unidentified developer noted in one section of the Carberp source. “This stupid thing does God-knows-what.”

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