Posts Tagged: Dell SecureWorks


2
Jun 14

‘Operation Tovar’ Targets ‘Gameover’ ZeuS Botnet, CryptoLocker Scourge

The U.S. Justice Department is expected to announce today an international law enforcement operation to seize control over the Gameover ZeuS botnet, a sprawling network of hacked Microsoft Windows computers that currently infects an estimated 500,000 to 1 million compromised systems globally. Experts say PCs infected with Gameover are being harvested for sensitive financial and personal data, and rented out to an elite cadre of hackers for use in online extortion attacks, spam and other illicit moneymaking schemes.

This graphic, from 2012, shows the decentralized nature of P2P network connectivity of 23,196 PCs infected with Gameover.  Image: Dell SecureWorks

This graphic, from 2012, shows the decentralized nature of P2P network connectivity of 23,196 PCs infected with Gameover. Image: Dell SecureWorks

The sneak attack on Gameover, dubbed “Operation Tovar,” began late last week and is a collaborative effort by investigators at the FBI, Europol, and the UK’s National Crime Agency; security firms CrowdStrike, Dell SecureWorks, SymantecTrend Micro and McAfee; and academic researchers at VU University Amsterdam and Saarland University in Germany. News of the action first came to light in a blog post published briefly on Friday by McAfee, but that post was removed a few hours after it went online.

Gameover is based on code from the ZeuS Trojan, an infamous family of malware that has been used in countless online banking heists. Unlike ZeuS — which was sold as a botnet creation kit to anyone who had a few thousand dollars in virtual currency to spend — Gameover ZeuS has since October 2011 been controlled and maintained by a core group of hackers from Russia and Ukraine.

Those individuals are believed to have used the botnet in high-dollar corporate account takeovers that frequently were punctuated by massive distributed-denial-of-service (DDoS) attacks intended to distract victims from immediately noticing the thefts. According to the Justice Department, Gameover has been implicated in the theft of more than $100 million in account takeovers.

The curators of Gameover also have reportedly loaned out sections of their botnet to vetted third-parties who have used them for a variety of purposes. One of the most popular uses of Gameover has been as a platform for seeding infected systems with CryptoLocker, a nasty strain of malware that locks your most precious files with strong encryption until you pay a ransom demand.

According to a 2012 research paper published by Dell SecureWorks, the Gameover Trojan is principally spread via Cutwail, one of the world’s largest and most notorious spam botnets (for more on Cutwail and its origins and authors, see this post). These junk emails typically spoof trusted brands, including shipping and phone companies, online retailers, social networking sites and financial institutions. The email lures bearing Gameover often come in the form of an invoice, an order confirmation, or a warning about an unpaid bill (usually with a large balance due to increase the likelihood that a victim will click the link). The links in the email have been replaced with those of compromised sites that will silently probe the visitor’s browser for outdated plugins that can be leveraged to install malware.

It will be interesting to hear how the authorities and security researchers involved in this effort managed to gain control over the Gameover botnet, which uses an advanced peer-to-peer (P2P) mechanism to control and update the bot-infected systems. Continue reading →


29
Jan 14

New Clues in the Target Breach

An examination of the malware used in the Target breach suggests that the attackers may have had help from a poorly secured feature built into a widely-used IT management software product that was running on the retailer’s internal network.

As I noted in  Jan. 15’s story — A First Look at the Target Intrusion, Malware — the attackers were able to infect Target’s point-of-sale registers with a malware strain that stole credit and debit card data. The intruders also set up a control server within Target’s internal network that served as a central repository for data hoovered up from all of the infected registers.

According to sources, "ttcopscli3acs" is the name of the Windows share point used by the POS malware planted at Target stores; the username that the thieves used to log in remotely and download stolen card data was "Best1_user"; the password was "BackupU$r"

“ttcopscli3acs” is the name of the Windows share used by the POS malware planted at Target stores; the username that malware used to upload stolen card data was “Best1_user”; the password was “BackupU$r”

That analysis looked at a malware component used in Target breach that was uploaded to Symantec’s ThreatExpert scanning service on Dec. 18 but which was later deleted (a local PDF copy of it is here). The ThreatExpert writeup suggests that the malware was responsible for moving stolen data from the compromised cash registers to that shared central repository, which had the internal address of 10.116.240.31. The “ttcopscli3acs” bit is the Windows domain name used on Target’s network. The user account “Best1_user” and password “BackupU$r” were used to log in to the shared drive (indicated by the “S:” under the “Resource Type” heading in the image above.

That “Best1_user” account name seems an odd one for the attackers to have picked at random, but there is a better explanation: That username is the same one that gets installed with an IT management software suite called Performance Assurance for Microsoft Servers. This product, according to its maker — Houston, Texas base BMC Software — includes administrator-level user account called “Best1_user.”

This knowledge base article (PDF) published by BMC explains the Best1_user account is installed by the software to do routine tasks. That article states that while the Best1_user account is essentially a “system” or “administrator” level account on the host machine, customers shouldn’t concern themselves with this account because “it is not a member of any group (not even the ‘users’ group) and therefore can’t be used to login to the system.”

“The only privilege that the account is granted is the ability to run as a batch job,” the document states, indicating that it could be used to run programs if invoked from a command prompt. Here’s my favorite part:

Perform Technical Support does not have the password to this account and this password has not be released by Perform Development. Knowing the password to the account should not be important as you cannot log into the machine using this account. The password is known internally and used internally by the Perform agent to assume the identity of the “Best1_user” account.”

I pinged BMC to find out if perhaps the password supplied in the Target malware (BackupU$r) is in fact the secret password for the Best1_user account. The company has so far remained silent on this question.

This was the hunch put forward by the Counter Threat Unit (CTU) of Dell SecureWorks in an analysis that was privately released to some of the company’s clients this week.

Relationships between compromised and attacker-controlled assets. Source: Dell Secureworks.

Relationships between compromised and attacker-controlled assets. Source: Dell Secureworks.

“Attackers exfiltrate data by creating a mount point for a remote file share and copying the data stored by the memory-scraping component to that share,” the SecureWorks paper notes. “In the previous listing showing the data’s move to an internal server, 10.116.240.31 is the intermediate server selected by attackers, and CTU researchers believe the “ttcopscli3acs” string is the Windows domain name used on Target’s network. The Best1_user account appears to be associated with the Performance Assurance component of BMC Software’s Patrol product. According to BMC’s documentation, this account is normally restricted, but the attackers may have usurped control to facilitate lateral movement within the network.

According to SecureWorks, one component of the malware installed itself as a service called “BladeLogic,” a service name no doubt designed to mimic another BMC product called BMC BladeLogic Automation Suite. BMC spokeswoman Ann Duhon said that the attackers were simply invoking BMC’s trademark to make the malicious program appear legitimate to the casual observer, but it seems likely that at least some BMC software was running inside of Target’s network, and that the attackers were well aware of it.

Update Jan. 30, 5:48 p.m.: BMC just issued the following statement:

There have been several articles in the press speculating about the Target breach.  BMC Software has received no information from Target or the investigators regarding the breach. In some of those articles, BMC products were mentioned in two different ways.

The first was a mention of a “bladelogic.exe” reference in the attack.   The executable name “bladelogic.exe” does not exist in any piece of legitimate BMC software.  McAfee has issued a security advisory stating that: “The reference to “bladelogic” is a method of obfuscation.  The malware does not compromise, or integrate with, any BMC products in any way.

The second reference was to a password that was possibly utilized as part of the attack, with the implication that it was a BMC password.  BMC has confirmed that the password mentioned in the press is not a BMC-generated password.

At this point, there is nothing to suggest that BMC BladeLogic or BMC Performance Assurance has a security flaw or was compromised as part of this attack.

Malware is a problem for all IT environments. BMC asks all of our customers to be diligent in ensuring that their environments are secure and protected.

I parse their statement to mean that the “BackupU$r” password referenced in the Target malware is not their software’s secret password. But nothing in the statement seems to rule out the possibility that the attackers leveraged a domain user account installed by BMC software to help exfiltrate card data from Target’s network.

Original story:

According to a trusted source who uses mostly open-source data to keep tabs on the software and hardware used in various retail environments, BMC’s software is in use at many major retail and grocery chains across the country, including Kroger, Safeway, Home Depot, Sam’s Club and The Vons Companies, among many others.

A copy of the SecureWorks report is here (PDF). It contains some fairly detailed analysis of this and other portions of the malware used in the Target intrusion. What it states up front that it does not have — and what we still have not heard from Target — is how the attackers broke in to begin with….

Continue reading →


5
Dec 13

ZeroAccess Botnet Down, But Not Out

Europol, Microsoft Kneecap Click-Fraud Botnet

Authorities in Europe joined Microsoft Corp. this week in disrupting “ZeroAccess,” a vast botnet that has enslaved more than two million PCs with malicious software in an elaborate and lucrative scheme to defraud online advertisers.

The action comes partly from Europol’s European Cybercrime Center (EC3), as well as law enforcement cybercrime units from Germany, Latvia, Switzerland and the Netherlands, countries that hosted many of the Internet servers used to control the ZeroAccess botnet.

In tandem with the law enforcement moves in Europe, Microsoft filed a civil lawsuit to unmask eight separate cybercriminals thought to be operating the giant botnet, and to block incoming and outgoing communications between infected PCs in the United States and those 18 control servers, according to a statement released by EC3.

The malware the powers the botnet, also known as “ZAccess” and “Sirefef,” is a complex threat that has evolved significantly since its inception in 2009. It began as a malware delivery platform that was used to spread other threats, such as fake antivirus software (a.k.a. “scareware”).

In recent years, however, the miscreants behind ZeroAccess rearchitected the botnet so that infected systems were forced to perpetrate a moneymaking scheme known as “click fraud” — the practice of fraudulently generating clicks on ads without any intention of fruitfully interacting with the advertiser’s site.

Maps of ZeroAccess infected PCs in Texas. Source: botnetlegalnotice.com

Maps of ZeroAccess infected PCs in Texas. Source: botnetlegalnotice.com

It remains unclear how much this coordinated action will impact the operations of ZeroAccess over the long term. Early versions of ZeroAccess relied on a series of control servers to receive updates, but recent versions of the botnet malware were designed to make the network as a whole more resilient and resistant to targeted takedowns such as the one executed this week.

Specifically, ZeroAccess employs a peer-to-peer (P2P) architecture in which new instructions and payloads are distributed from one infected host to another. P2P-based botnets are designed to eliminate a single point of failure, so that if one node used to control the botnet is knocked offline, the remainder of the botnet can still function.

The actions this week appear to have targeted the servers that deliver a specific component of ZeroAccess that gives infected systems new instructions on how to defraud various online advertisers — including Microsoft. While this effort will not disable the ZeroAccess botnet (the infected systems will likely remain infected), it should allow Microsoft to determine which online affiliates and publishers are associated with the miscreants behind ZeroAccess, since those publishers will have stopped sending traffic directly after the takedown occurred.

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26
Sep 12

Chinese Hackers Blamed for Intrusion at Energy Industry Giant Telvent

A company whose software and services are used to remotely administer and monitor large sections of the energy industry began warning customers last week that it is investigating a sophisticated hacker attack spanning its operations in the United States, Canada and Spain. Experts say digital fingerprints left behind by attackers point to a Chinese hacking group tied to repeated cyber-espionage campaigns against key Western interests.

The attack comes as U.S. policymakers remain gridlocked over legislation designed to beef up the cybersecurity posture of energy companies and other industries that maintain some of the world’s most vital information networks.

In letters sent to customers last week, Telvent Canada Ltd. said that on Sept. 10, 2012 it learned of a breach of its internal firewall and security systems. Telvent said the attacker(s) installed malicious software and stole project files related to one of its core offerings — OASyS SCADA — a product that helps energy firms mesh older IT assets with more advanced “smart grid” technologies.

The firm said it was still investigating the incident, but that as a precautionary measure, it had disconnected the usual data links between clients and affected portions of its internal networks.

“In order to be able to continue to provide remote support services to our customers in a secure manner, we have established new procedures to be followed until such time as we are sure that there are not further intrusions into the Telvent network and that all virus or malware files have been eliminated,” the company said in a letter mailed to customers this week, a copy of which was obtained by KrebsOnSecurity.com. “Although we do not have any reason to believe that the intruder(s) acquired any information that would enable them to gain access to a customer system or that any of the compromised computers have been connected to a customer system, as a further precautionary measure, we indefinitely terminated any customer system access by Telvent.”

The incident is the latest reminder of problems that can occur when corporate computer systems at critical networks are connected to sensitive control systems that were never designed with security in mind. Security experts have long worried about vulnerabilities being introduced into the systems that regulate the electrical grid as power companies transferred control of generation and distribution equipment from internal networks to so-called “supervisory control and data acquisition,” or SCADA, systems that can be accessed through the Internet or by phone lines. The move to SCADA systems boosts efficiency at utilities because it allows workers to operate equipment remotely, but experts say it also exposes these once-closed systems to cyber attacks.

Telvent did not respond to several requests for comment. But in a series of written communications to clients, the company detailed ongoing efforts to ascertain the scope and duration of the breach. In those communications, Telvent said it was working with law enforcement and a task force of representatives from its parent firm, Schneider Electric, a French energy conglomerate that employs 130,000 and has operations across the Americas, Western Europe and Asia. Telvent reportedly employs about 6,000 people in at least 19 countries around the world.

The disclosure comes just days after Telvent announced it was partnering with Foxborough, Mass. based Industrial Defender to expand its cybersecurity capabilities within Telvent’s key utility and critical infrastructure solutions. A spokesperson for Industrial Defender said the company does not comment about existing customers. Continue reading →


19
Sep 12

Malware Dragnet Snags Millions of Infected PCs

Last week, Microsoft Corp. made headlines when it scored an unconventional if not unprecedented legal victory: Convincing a U.S. court to let it seize control of a Chinese Internet service provider’s network as part of a crackdown on piracy.

I caught up with Microsoft’s chief legal strategist shortly after that order was executed, in a bid to better understand what they were seeing after seizing control over more than 70,000 domains that were closely associated with distributing hundreds of strains of malware. Microsoft said that within hours of the takeover order being granted, it saw more than 35 million unique Internet addresses phoning home to those 70,000 malicious domains.

First, the short version of how we got here: Microsoft investigators found that computer stores in China were selling PCs equipped with Windows operating system versions that were pre-loaded with the “Nitol” malware, and that these systems were phoning home to subdomains at 3322.org. The software giant subsequently identified thousands of sites at 3322.org that were serving Nitol and hundreds of other malware strains, and convinced a federal court in Virginia to grant it temporary control over portions of the dynamic DNS provider.

Microsoft was able to do that because – while 3322.org is owned by a firm in China — the dot-org registry is run by a company based in Virginia. Yet, as we can see from the graphic above provided by Microsoft, Nitol infections were actually the least of the problems hosted at 3322.org (more on this later).

To learn more about the outcome of the seizure, I spoke with Richard Boscovich, a senior attorney with the company’s digital crimes unit (DCU) who helped to coordinate this action and previous legal sneak attacks against malware havens. Our interview came just hours after Microsoft had been cleared to seize control over the 70,000+ subdomains at 3322.org. I asked Boscovich to describe what the company was seeing.

“The numbers are quite large,” he said. “Just a quick view of what we’ve been seeing so far is upwards of 35 million unique IP [addresses] trying to connect with the 70,000 subdomains.”

Certainly IP addresses can be very dynamic — a single computer can have multiple IP addresses over a period of a few days, for example. But even if there were half as many infected PCs than unique IPs that Microsoft observed reporting to those 70,000 domains, we’d still be talking about an amalgamation of compromised PCs that is far larger than any known botnet on the planet today.  So how certain was Microsoft that these 35 million unique IPs were in fact infected computers?

“We started identifying what our AV company blocks,” Boscovich explained. “We saw a lot of different types of malware, from keyloggers to DDoS tools and botnets going back there. Our position would be if you’re reaching out to these 70,000 subdomains, that the purpose would be you’re directed there to be infected or you are already infected with something. And that something was up to 560 or so malware strains we identified [tracing back] to 3322.org.”

COLLATERAL DAMAGE?

Microsoft’s past unilateral actions against malware purveyors and botnets have engendered their share of harsh reactions from members of the security community, and I fully expected this one also would be controversial. I wasn’t disappointed: Writing for Internet policy news site CircleID, longtime antispam activist Suresh Ramasubramanian warned that Microsoft’s action would cause “extremely high collateral damage,” both to innocent sites and to ongoing investigations.

“So, in the medium to long term run …all that Microsoft DCU and Mr. Boscovich have achieved are laudatory quotes in various newspapers and a public image as fearless and indefatigable fighters waging a lone battle against cybercrime,” Ramasubramanian wrote. “That manifestly is not the case. There are several other organizations (corporations, independent security researchers, law enforcement across several countries) that are involved in studying and mitigating botnets, and a lot of their work just gets abruptly disrupted (jeopardizing ongoing investigations, destroying evidence and carefully planted monitoring).”

Continue reading →


13
Sep 12

Microsoft Disrupts ‘Nitol’ Botnet in Piracy Sweep

Microsoft said Thursday that it convinced a U.S. federal court to grant it control over a botnet believed to be closely linked to counterfeit versions Windows that were sold in various computer stores across China. The legal victory also highlights a Chinese Internet service that experts say has long been associated with targeted, espionage attacks against U.S. and European corporations.

Source: Microsoft.com

Microsoft said it sought to disrupt a counterfeit supply-chain operation that sold knockoff versions of Windows PCs that came pre-loaded with a strain of malware called “Nitol,” which lets attackers control the systems from afar for a variety of nefarious purposes.

In legal filings unsealed Thursday by the U.S. District Court for the Eastern District of Virginia, Microsoft described how its researchers purchased computers from various cities in China, and found that approximately 20 percent of them were already infected with Nitol.

It’s not clear precisely how many systems are infected with Nitol, but it does not appear to be a particularly major threat. Microsoft told the court that it had detected nearly 4,000 instances of Windows computers infected with some version of the malware, but that this number likely represented “only a subset of the number of infected computers.” The company said the majority of Nitol infections and Internet servers used to control the botnet were centered around China, although several U.S. states — including California, New York and Pennsylvania — were home to significant numbers of compromised hosts.

Dubbed “Operation b70” by Microsoft, the courtroom maneuvers are the latest in a series of legal stealth attacks that the software giant has executed against large-scale cybercrime operations. Previous targets included the Waledac, Rustock, Kelihos and ZeuS botnets.

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30
Jul 12

Tagging and Tracking Espionage Botnets

A security researcher who’s spent 18 months cataloging and tracking malicious software that was developed and deployed specifically for spying on governments, activists and industry executives says the complexity and scope of these cyberspy networks now rivals many large conventional cybercrime operations.

Joe Stewart, senior director of malware research at Atlanta-based Dell SecureWorks, said he’s tracked more than 200 unique families of custom malware used in cyber-espionage campaigns. He also uncovered some 1,100 Web site names registered by cyberspies for hosting networks used to control the malware, or for “spear phishing,” highly targeted emails that spread the malware.

Although those numbers may seem low in the grand scheme of things (antivirus companies now deal with many tens of thousands of new malware samples each day), almost everything about the way these cyberspying networks are put together seems designed to mask the true scope of the operations, he found. For instance, Stewart discovered that the attackers set up almost 20,000 subdomains on those 1,100 domain names; but these subdomains were used for controlling or handing out new malware for botnets that each only controlled a few hundred computers at a time.

“Unlike the largest cybercrime networks that can contain millions of infected computers in a single botnet, cyber-espionage encompasses tens of thousands of infected computers spread across hundreds of botnets,” Stewart wrote in a paper released at last week’s Black Hat security convention in Las Vegas. “So each botnet…tends to look like a fairly small-scale operation. But this belies the fact that for every [cyber-espionage] botnet that is discovered and publicized, hundreds more continue to lie undetected on thousands of networks.”

Once you get past all the technical misdirection built into the malware networks by its architects, Stewart said, the infrastructure that frames these spy machines generally points in one of two directions: one group’s infrastructure points back to Shanghai, the other to Beijing.

“There have to be hundreds of people involved, just to maintain this amount of infrastructure and this much activity and this many spear phishes, collecting so many documents, and writing this much malware,” Stewart said. “But when it comes time to grouping them, that’s when it gets harder. What I can tell from the clustering I’m doing here is that there are two major groups in operation. Some have dozens of different malware families that they use, but many will share a common botnet command and control infrastructure.”

Domains connected to different cyber-espionage botnets typically trace back to one of two destinations in China, according to Dell SecureWorks.

Continue reading →


21
Nov 11

DDoS Attack on KrebsOnSecurity.com

Last week, not long after I published the latest installment in my Pharma Wars series, KrebsOnSecurity.com was the target of a sustained distributed denial-of-service (DDoS) attack that caused the site to be unavailable for some readers between Nov. 17 and 18. What follows are some details about that attack, and how it compares to previous intimidation attempts.

The DDoS was caused by incessant, garbage requests from more than 20,000+ PCs around the globe infected with malware  that allows criminals to control them remotely for nefarious purposes. If you’ve noticed that a few of the features on this site haven’t worked as usual these past few days, now you know why. Thanks for your patience.

I shared the log files of the attack with Joe Stewart, director of malware research at Dell SecureWorks. Stewart discovered that the botnet responsible for hitting my site appears to have been created with Russkill, a commercial crimeware kit that is sold for a few hundred bucks on the hacker underground. Russkill, sometimes called Dirt Jumper, does its dirty work by forcing infected systems to rapidly request the targeted site’s homepage.

Stewart said he suspects — but can’t prove – that the control center for this botnet is noteye.biz, based on traffic analysis of Internet addresses in the logs I shared with him.

“I did not already have [noteye.biz] under monitoring so it is impossible to say for sure what targets were hit in the past,” Stewart wrote in an email. He noted that the same attacker also apparently runs a Dirt Jumper botnet at xzrw1q.com, which also is currently attacking Ukrainian news site genshtab.censor.net.ua, and kidala.info (“kidala” is Russian slang for “criminal,” and kidala.info is a well-known Russian crime forum).

“According to my logs this botnet did attack your site back in April, so this is some additional circumstantial evidence that suggests the noteye.biz [control network] may have been involved in the recent attack on your site,” Stewart wrote.

As Stewart notes, this is not the first time my site has been pilloried, although it was arguably the most disruptive. In October 2010, a botnet typically used to spread spam for rogue Internet pharmacies attacked krebsonsecurity.com, using a hacked Linux server at a research lab at Microsoft, of all places.

I’ve spoken at more than a dozen events this year, and the same question nearly always comes up: Do you ever get threatened or attacked? For the most part, the majority of the threats or intimidation attempts have been light-hearted.

Yes, occasionally crooks in the underground will get a bit carried away – as in these related threads from an exclusive crime forum, where I am declared the “enemy of carding;” or in the love I received from the guys at Crutop.nu, a major Russian adult Webmaster forum (the site now lives at Crutop.eu).

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1
Aug 11

Digital Hit Men for Hire

Cyber attacks designed to knock Web sites off line happen every day, yet shopping for a virtual hit man to launch one of these assaults has traditionally been a dicey affair. That’s starting to change: Hackers are openly competing to offer services that can take out a rival online business or to settle a score.

An ad for a DDoS attack service.

There are dozens of underground forums where members advertise their ability to execute debilitating “distributed denial-of-service” or DDoS attacks for a price. DDoS attack services tend to charge the same prices, and the average rate for taking a Web site offline is surprisingly affordable: about $5 to $10 per hour; $40 to $50 per day; $350-$400 a week; and upwards of $1,200 per month.

Of course, it pays to read the fine print before you enter into any contract. Most DDoS services charge varying rates depending on the complexity of the target’s infrastructure, and how much lead time the attack service is given to size up the mark. Still, buying in bulk always helps: One service advertised on several fraud forums offered discounts for regular and wholesale customers.

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