Krebs on Security

Arrests Tied to Citadel, Dridex Malware

September 7, 2015

Authorities in Europe have arrested alleged key players behind the development and deployment of sophisticated banking malware, including Citadel and Dridex. The arrests involved a Russian national and a Moldovan man, both of whom were traveling or residing outside of their native countries and are now facing extradition to the United States.

Last week, a 30-year-old from Moldova who was wanted by U.S. authorities was arrested in Paphos — a coastal vacation spot in Cyprus where the accused was reportedly staying with his wife. A story in the Cyprus Mail has few other details about the arrest, other than to say authorities believe the man was responsible for more than $3.5 million in bank fraud using a PC.

Sources close to the investigation say the man is a key figure in an organized crime gang responsible for developing and using a powerful banking Trojan known as “Dridex” (a.k.a. Cridex, Bugat). The Dridex gang is thought to have spun off from the “Business Club,” an Eastern European organized cybercrime gang accused of stealing more than $100 million from banks and businesses worldwide.

In June 2014, the U.S. Justice Department joined multiple international law enforcement agencies and security firms in taking down the Business Club’s key asset: The Gameover ZeuS botnet, an ultra-sophisticated, global crime machine that infected upwards of a half-million PCs and was used in countless cyberheists. Dridex would first emerge in July 2014, a month after the Gameover Zeus botnet was dismantled.

Separately, the press in Norway writes about a 27-year-old Russian man identified only as “Mark” who was reportedly arrested in the Norwegian town of Fredrikstad at the request of the FBI. The story notes that American authorities believe Mark is the software developer behind Citadel, a malware-as-a-service product that played a key role in countless cyberheists against American and European small businesses.

For example, Citadel was thought to have been the very same malware used to steal usernames and passwords from a Pennsylvania heating and air conditioning vendor; those same stolen credentials were reportedly leveraged in the breach that resulted in the theft of nearly 40 million credit cards from Target Corp. in November and December of 2013.

The Norwegian newspaper VG writes that Mark has been held under house arrest for the past 11 months, while the FBI tries to work out his extradition to the United States. His detention is being fought by Russia, which is naturally opposed to the treatment he may receive in the United States and says the evidence against Mark is scant.

According to VG, the U.S. Justice Department believes Mark is none other than “Aquabox,” the nickname chosen by the proprietor of the Citadel malware, which was created based off of the source code for the ZeuS Trojan malware. Citadel was sold and marketed as a service that let buyers and users interact with the developer and one another, to solicit feedback on how to fix bugs in the malware program, and to request new features in the malware going forward.

For a full translation of the original Citadel sales pitch as penned by Aquabox in 2011, see this link (PDF). For a full translated version of the VG story on Mark, see this PDF (thanks to KrebsOnSecurity reader Jeevan Sivagnanasuntharam for helping with the translation). VG notes that Mark continues to maintain his innocence. [Side note: The Citadel malware has for years had in its code a dig directed at the author of this blog: Included in the guts of the Trojan is the text string, “Coded by BRIAN KREBS for personal use only. I love my job & wife.” Needless to say, the second part of that statement is true, but Citadel was not coded by this Brian Krebs.]

A text string inside of the Citadel trojan. Source: AhnLab

Ars Technica carries an interesting piece about Deniss Calovskis, a Latvian man who was arrested in February and extradited to the United States for his role in creating the Gozi virus, another powerful malware family that has been used in countless cyberheists. The 30-year-old Calovskis long maintained his innocence, but ultimately acknowledged his role in a guilty plea entered in a federal court in Manhattan last week. Continue reading →

More ATM “Insert Skimmer” Innovations

September 3, 2015

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Most of us know to keep our guard up when withdrawing cash from an ATM and to look for any signs that the machine may have been tampered with. But ATM fraud experts say they continue to see criminal innovations with “insert skimmers,” wafer-thin data theft devices that fit inside the ATM’s card acceptance slot and do not alter the outward appearance of a compromised cash machine.

The insert skimmer pictured below was recently pulled from an ATM in Europe. According to a report by the European ATM Security Team (EAST), this type of device is inserted through the card reader throat and then sits inside the card reader capturing the data of cards that are subsequently inserted.

An insert skimmer. Image: EAST.

Of course, an insert skimmer alone isn’t going to capture your PIN. For that, thieves typically rely on cleverly hidden tiny cameras. Often, the spy camera is tucked inside a false panel above or directly beside the PIN pad. But as I’ve noted in stories about skimming attacks that never touch the ATM (such as vestibule door skimmers), crooks often get very creative, hiding cameras behind things like convex mirrors — or even phony fire alarms.

The image below was captured last year by a U.S.-based bank’s own ATM security camera. It shows a skimmer scammer getting ready to install a tiny camera hidden inside of a fake fire alarm.

Hidden cameras made to work in tandem with skimming devices need not be hidden on the compromised ATM itself.

Continue reading →

OPM (Mis)Spends $133M on Credit Monitoring

September 2, 2015

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The Office of Personnel Management (OPM) has awarded a $133 million contract to a private firm in an effort to provide credit monitoring services for three years to nearly 22 million people who had their Social Security numbers and other sensitive data stolen by cybercriminals. But perhaps the agency should be offering the option to pay for the cost that victims may incur in “freezing” their credit files, a much more effective way of preventing identity theft.

Not long after news broke that Chinese hackers had stolen SSNs and far more sensitive data on 4.2 million individuals — including background investigations, fingerprint data, addresses, medical and mental-health history, and financial history — OPM announced it had awarded a contract worth more than $20 million to Austin, Texas-based identity protection firm CSID to provide 18 months of protection for those affected.

Soon after the CSID contract was awarded, the OPM acknowledged that the breach actually impacted more than five times as many individuals as originally thought. In response, the OPM has awarded a $133 million contract to Portland, Ore. based ID Experts.

No matter how you slice it, $133 million is a staggering figure for a service that in all likelihood will do little to prevent identity thieves from hijacking the names, good credit and good faith of breach victims. While state-sponsored hackers thought to be responsible for this breach were likely interested in the data for more strategic than financial reasons (recruiting, discovering and/or thwarting spies), the OPM should not force breach victims to pay for true protection.

As I’ve noted in story after story, identity protection services like those offered by CSID, Experian and others do little to block identity theft: The most you can hope for from these services is that they will notify you after crooks have opened a new line of credit in your name. Where these services do excel is in helping with the time-consuming and expensive process of cleaning up your credit report with the major credit reporting agencies.

Many of these third party services also induce people to provide even more information than was leaked in the original breach. For example, CSID offers the ability to “monitor thousands of websites, chat rooms, forums and networks, and alerts you if your personal information is being bought or sold online.” But in order to use this service, users are encouraged to provide bank account and credit card data, passport and medical ID numbers, as well as telephone numbers and driver’s license information.

The only step that will reliably block identity thieves from accessing your credit file — and therefore applying for new loans, credit cards and otherwise ruining your good name — is freezing your credit file with the major credit bureaus. This freeze process — described in detail in the primer, How I Learned to Stop Worrying and Embrace the Security Freeze — can be done online or over the phone. Each bureau will give the consumer a unique personal identification number (PIN) that the consumer will need to provide in the event that he needs to apply for new credit in the future.

But there’s a catch: Depending on the state in which you reside, the freeze can cost $5 to $15 per credit bureau. Also, in some states consumers can be charged a fee to temporarily lift the freeze. Continue reading →

Like Kaspersky, Russian Antivirus Firm Dr.Web Tested Rivals

September 1, 2015

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A recent Reuters story accusing Russian security firm Kaspersky Lab of faking malware to harm rivals prompted denials from the company’s eponymous chief executive — Eugene Kaspersky — who called the story “complete BS” and noted that his firm was a victim of such activity. But according to interviews with the CEO of Dr.Web — Kaspersky’s main competitor in Russia — both companies experimented with ways to expose antivirus vendors who blindly accepted malware intelligence shared by rival firms.

The Reuters piece cited anonymous, former Kaspersky employees who said the company assigned staff to reverse-engineer competitors’ virus detection software to figure out how to fool those products into flagging good files as malicious. Such errors, known in the industry as “false positives,” can be quite costly, disruptive and embarrassing for antivirus vendors and their customers.

Reuters cited an experiment that Kaspersky first publicized in 2010, in which a German computer magazine created ten harmless files and told antivirus scanning service Virustotal.com that Kaspersky detected them as malicious (Virustotal aggregates data on suspicious files and shares them with security companies). The story said the campaign targeted antivirus products sold or given away by AVG, Avast and Microsoft.

“Within a week and a half, all 10 files were declared dangerous by as many as 14 security companies that had blindly followed Kaspersky’s lead, according to a media presentation given by senior Kaspersky analyst Magnus Kalkuhl in Moscow in January 2010,” wrote Reuters’ Joe Menn. “When Kaspersky’s complaints did not lead to significant change, the former employees said, it stepped up the sabotage.”

Eugene Kaspersky posted a lengthy denial of the story on his personal blog, calling the story a “conflation of a number of facts with a generous amount of pure fiction.” But according to Dr.Web CEO Boris Sharov, Kaspersky was not alone in probing which antivirus firms were merely aping the technology of competitors instead of developing their own.

Dr.Web CEO Boris Sharov.

In an interview with KrebsOnSecurity, Sharov said Dr.Web conducted similar analyses and reached similar conclusions, although he said the company never mislabeled samples submitted to testing labs.

“We did the same kind of thing,” Sharov said. “We went to the [antivirus] testing laboratories and said, ‘We are sending you clean files, but a little bit modified. Could you please check what your system says about that?'”

Sharov said the testing lab came back very quickly with an answer: Seven antivirus products detected the clean files as malicious.

“At this point, we were very confused, because our explanation was very clear: ‘We are sending you clean files. A little bit modified, but clean, harmless files,'” Sharov recalled of an experiment the company said it conducted over three years ago. “We then observed the evolution of these two files, and a week later, half of the antivirus products were flagging them as bad. But we never flagged these ourselves as bad.”

Sharov said the experiments by both Dr.Web and Kaspersky — although conducted differently and independently — were attempts to expose the reality that many antivirus products are simply following the leaders.

“The security industry in that case becomes bullshit, because people believe in those products and use them in their corporate environments without understanding that those products are just following others,” Sharov said. “It’s unacceptable.”

According to Sharov, a good antivirus product actually consists of two products: One that is sold to customers in a box and/or or online, and the second component that customers will never see — the back-end internal infrastructure of people, machines and databases that are constantly scanning incoming suspicious files and testing the overall product for quality assurance. Such systems, he said, include exhaustive “clean file” tests, which scan incoming samples to make sure they are not simply known, good files. Programs that have never been seen before are nearly always given more scrutiny, but they also are a frequent source of false positives.

“We have sometimes false positives because we are unable to gather all the clean files in the world,” Sharov said. “We know that we can get some part of them, but pretty sure we never get 100 percent. Anyway, this second part of the [antivirus product] should be much more powerful, to make sure what you release to public is not harmful or dangerous.”

Sharov said some antivirus firms (he declined to name which) have traditionally not invested in all of this technology and manpower, but have nevertheless gained top market share.

“For me it’s not clear that [Kaspersky Lab] would have deliberately attacked other antivirus firm, because you can’t attack a company in this way if they don’t have the infrastructure behind it,” Sharov said. Continue reading →

Six Nabbed for Using LizardSquad Attack Tool

August 28, 2015

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Authorities in the United Kingdom this week arrested a half-dozen young males accused of using the Lizard Squad’s Lizard Stresser tool, an online service that allowed paying customers to launch attacks capable of taking Web sites offline for up to eight hours at a time.

The Lizard Stresser came to prominence not long after Christmas Day 2014, when a group of young n’er-do-wells calling itself the Lizard Squad used the tool to knock offline the Sony Playstation and Microsoft Xbox gaming networks. As first reported by KrebsOnSecurity on Jan. 9, the Lizard Stresser drew on Internet bandwidth from hacked home Internet routers around the globe that are protected by little more than factory-default usernames and passwords. The LizardStresser service was hacked just days after that Jan. 9 story, and disappeared shortly after that.

The Lizard Stresser’s add-on plans. In case it wasn’t clear, this service was *not* sponsored by Brian Krebs as suggested in the screenshot.

“Those arrested are suspected of maliciously deploying Lizard Stresser, having bought the tool using alternative payment services such as Bitcoin in a bid to remain anonymous,” reads a statement from the U.K.’s National Crime Agency (NCA). “Organisations believed to have been targeted by the suspects include a leading national newspaper, a school, gaming companies and a number of online retailers.” Continue reading →

FBI: $1.2B Lost to Business Email Scams

August 27, 2015

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The FBI today warned about a significant spike in victims and dollar losses stemming from an increasingly common scam in which crooks spoof communications from executives at the victim firm in a bid to initiate unauthorized international wire transfers. According to the FBI, thieves stole nearly $750 million in such scams from more than 7,000 victim companies in the U.S. between October 2013 and August 2015.

In January 2015, the FBI released stats showing that between Oct. 1, 2013 and Dec. 1, 2014, some 1,198 companies lost a total of $179 million in so-called business e-mail compromise (BEC) scams, also known as “CEO fraud.” The latest figures show a marked 270 percent increase in identified victims and exposed losses. Taking into account international victims, the losses from BEC scams total more than $1.2 billion, the FBI said.

“The scam has been reported in all 50 states and in 79 countries,” the FBI’s alert notes. “Fraudulent transfers have been reported going to 72 countries; however, the majority of the transfers are going to Asian banks located within China and Hong Kong.”

CEO fraud usually begins with the thieves either phishing an executive and gaining access to that individual’s inbox, or emailing employees from a look-alike domain name that is one or two letters off from the target company’s true domain name. For example, if the target company’s domain was “example.com” the thieves might register “examp1e.com” (substituting the letter “L” for the numeral 1) or “example.co,” and send messages from that domain.

Unlike traditional phishing scams, spoofed emails used in CEO fraud schemes are unlikely to set off spam traps, because these are targeted phishing scams that are not mass e-mailed. Also, the crooks behind them take the time to understand the target organization’s relationships, activities, interests and travel and/or purchasing plans.

They do this by scraping employee email addresses and other information from the target’s Web site to help make the missives more convincing. In the case where executives or employees have their inboxes compromised by the thieves, the crooks will scour the victim’s email correspondence for certain words that might reveal whether the company routinely deals with wire transfers — searching for messages with key words like “invoice,” “deposit” and “president.”

On the surface, business email compromise scams may seem unsophisticated relative to moneymaking schemes that involve complex malicious software, such as Dyre and ZeuS. But in many ways, the BEC attack is more versatile and adept at sidestepping basic security strategies used by banks and their customers to minimize risks associated with account takeovers. In traditional phishing scams, the attackers interact with the victim’s bank directly, but in the BEC scam the crooks trick the victim into doing that for them. Continue reading →

Who Hacked Ashley Madison?

August 26, 2015

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AshleyMadison.com, a site that helps married people cheat and whose slogan is “Life is Short, have an Affair,” recently put up a half million (Canadian) dollar bounty for information leading to the arrest and prosecution of the Impact Team — the name chosen by the hacker(s) who recently leaked data on more than 30 million Ashley Madison users. Here is the first of likely several posts examining individuals who appear to be closely connected to this attack.

It was just past midnight on July 20, a few hours after I’d published an exclusive story about hackers breaking into AshleyMadison.com. I was getting ready to turn in for the evening when I spotted a re-tweet from a Twitter user named Thadeus Zu (@deuszu) who’d just posted a link to the same cache of data that had been confidentially shared with me by the Impact Team via the contact form on my site just hours earlier: It was a link to the proprietary source code for Ashley Madison’s service.

Initially, that tweet startled me because I couldn’t find any other sites online that were actually linking to that source code cache. I began looking through his past tweets and noticed some interesting messages, but soon enough other news events took precedence and I forgot about the tweet.

I revisited Zu’s tweet stream again this week after watching a press conference held by the Toronto Police (where Avid Life Media, the parent company of Ashley Madison, is based). The Toronto cops mostly recapped the timeline of known events in the hack, but they did add one new wrinkle: They said Avid Life employees first learned about the breach on July 12 (seven days before my initial story) when they came into work, turned on their computers and saw a threatening message from the Impact Team accompanied by the anthem “Thunderstruck” by Australian rock band AC/DC playing in the background.

After writing up a piece on the bounty offer, I went back and downloaded all five years’ worth of tweets from Thadeus Zu, a massively prolific Twitter user who typically tweets hundreds if not thousands of messages per month. Zu’s early years on Twitter are a catalog of simple hacks — commandeering unsecured routers, wireless cameras and printers — as well as many, many Web site defacements.

On the defacement front, Zu focused heavily on government Web sites in Asia, Europe and the United States, and in several cases even taunted his targets. On Aug. 4, 2012, he tweeted to KPN-CERT, a computer security incident response team in the Netherlands, to alert the group that he’d hacked their site. “Next time, it will be Thunderstruck. #ACDC” Zu wrote.

The day before, he’d compromised the Web site for the Australian Parliament, taunting lawmakers there with the tweet: “Parliament of Australia bit.ly/NPQdsP Oi! Oi! Oi!….T.N.T. Dynamite! Listen to ACDC here.”

I began to get very curious about whether there were any signs on or before July 19, 2015 that Zu was tweeting about ACDC in relation to the Ashley Madison hack. Sure enough: At 9:40 a.m., July 19, 2015 — nearly 12 hours before I would first be contacted by the Impact Team — we can see Zu is feverishly tweeting to several people about setting up “replication servers” to “get the show started.” Can you spot what’s interesting in the tabs on his browser in the screenshot he tweeted that morning?

Twitter user ThadeusZu tweets about setting up replication servers. Did you spot the Youtube video he’s playing when he took this screenshot?

Ten points if you noticed the Youtube.com tab showing that he’s listening to AC/DC’s “Thunderstruck.”

A week ago, the news media pounced on the Ashley Madison story once again, roughly 24 hours after the hackers made good on their threat to release the Ashley Madison user database. I went back and examined Zu’s tweet stream around that time and found he beat Wired.com, ArsTechnica.com and every other news media outlet by more than 24 hours with the Aug. 17 tweet, “Times up,” which linked to the Impact Team’s now infamous post listing the sites where anyone could download the stolen Ashley Madison user database.

ThadeusZu tweeted about the downloadable Ashley Madison data more than 24 hours before news outlets picked up on the cache.

Continue reading →

Leaked AshleyMadison Emails Suggest Execs Hacked Competitors

August 24, 2015

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Hacked online cheating service AshleyMadison.com is portraying itself as a victim of malicious cybercriminals, but leaked emails from the company’s CEO suggest that AshleyMadison’s top leadership hacked into a competing dating service in 2012.

AshleyMadison CEO Noel Biderman. Source: Twitter.

Late last week, the Impact Team — the hacking group that has claimed responsibility for leaking personal data on more than 30 million AshleyMadison users — released a 30-gigabyte archive that it said were emails lifted from AshleyMadison CEO Noel Biderman.

A review of those missives shows that on at least one occasion, a former company executive hacked another dating website, exfiltrating their entire user database. On Nov. 30, 2012, Raja Bhatia, the founding chief technology officer of AshleyMadison.com, sent a message to Biderman notifying his boss of a security hole discovered in nerve.com, an American online magazine dedicated to sexual topics, relationships and culture.

At the time, nerve.com was experimenting with its own adult dating section, and Bhatia said he’d uncovered a way to download and manipulate the nerve.com user database.

“They did a very lousy job building their platform. I got their entire user base,” Bhatia told Biderman via email, including in the message a link to a Github archive with a sample of the database. “Also, I can turn any non paying user into a paying user, vice versa, compose messages between users, check unread stats, etc.”

Neither Bhatia nor Biderman could be immediately reached for comment. KrebsOnSecurity.com spoke with Bhatia last week after the Impact Team made good on its threat to release the Ashley Madison user database. At the time, Bhatia was downplaying the leak, saying that his team of investigators had found no signs that the dump of data was legitimate, and that it looked like a number of fake data dumps the company had seen in the weeks prior. Hours later, the leak had been roundly confirmed as legitimate by countless users on Twitter who were able to find their personal data in the cache of account information posted online.

The leaked Biderman emails show that a few months before Bhatia infiltrated Nerve.com, AshleyMadison’s parent firm — Avid Life Media — was approached with an offer to partner with and/or invest in the property. Email messages show that Bhatia initially was interested enough to offer at least $20 million for the company along with a second property called flirts.com, but that AshleyMadison ultimately declined to pursue a deal.

More than six months after Bhatia came to Biderman with revelations of the nerve.com security vulnerabilities, Biderman was set to meet with several representatives of the company. “Should I tell them of their security hole?” Biderman wrote to Bhatia, who doesn’t appear to have responded to that question via email. Continue reading →

AshleyMadison: $500K Bounty for Hackers

August 24, 2015

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AshleyMadison.com, an online cheating service whose motto is “Life is Short, Have an Affair,” is offering a $500,000 reward for information leading to the arrest and prosecution of the individual or group of people responsible for leaking highly personal information on the company’s more than 30 million users.

A snippet of the message left behind by the Impact Team.

The bounty offer came at a press conference today by the police in Toronto — where AshleyMadison is based. At the televised and Webcast news conference, Toronto Police Staff Superintendant Bryce Evans recounted the key events in “Project Unicorn,” the code name law enforcement officials have assigned to the investigation into the attack. In relaying news of the reward offer, Evans appealed to the public and “white hat” hackers for help in bringing the attackers to justice.

“The ripple effect of the impact team’s actions has and will continue to have a long term social and economic impacts, and they have already sparked spin-offs of crimes and further victimization,” Evans said. “As of this morning, we have two unconfirmed reports of suicides that are associated [with] the leak of AshleyMadison customer profiles.”

Evans did not elaborate on the suicides, saying only that his office is investigating those reports. The San Antonio Express-News reported Friday that a city worker whose information was found in the leaked AshleyMadison database took his life last Thursday, although the publication acknowledges that it’s unclear whether the worker’s death had anything to do with the leak.

Evans warned the public and concerned AshleyMadison users to be on guard against a raft of extortion scams that are already popping up and targeting the site’s customers. On Friday, KrebsOnSecurity featured an exclusive story about one such extortion scheme that threatened to alert the victim’s spouse unless the recipient paid the attacker a Bitcoin (worth slightly more than USD $250). The Toronto Police posted this image of a similar extortion attempt that they have seen making the rounds.

“Criminals have already engaged in online scams by claiming to provide access to the leaked web site,” he said. “The public needs to be aware that by clicking on these links, you are exposing your computer to adware and spyware and viruses. Also there are those offering to erase customer profiles from the list. Nobody is going to be able to erase that information.” Continue reading →

Extortionists Target Ashley Madison Users

August 21, 2015

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People who cheat on their partners are always open to extortion by the parties involved. But when the personal details of millions of cheaters get posted online for anyone to download — as is the case with the recent hack of infidelity hookup site AshleyMadison.com — random blackmailers are bound to pounce on the opportunity.

An extortion email sent to an AshleyMadison user.

According to security firms and to a review of several emails shared with this author, extortionists already see easy pickings in the leaked AshleyMadison user database.

Earlier today I heard from Rick Romero, the information technology manager at VF IT Services, an email provider based in Milwaukee. Romero said he’s been building spam filters to block outgoing extortion attempts against others from rogue users of his email service. Here’s one that he blocked this morning (I added a link to the bitcoin address in the message, which shows nobody has paid into this particular wallet yet):

Hello,

Unfortunately, your data was leaked in the recent hacking of Ashley Madison and I now have your information.

If you would like to prevent me from finding and sharing this information with your significant other send exactly 1.0000001 Bitcoins (approx. value $225 USD) to the following address:

1B8eH7HR87vbVbMzX4gk9nYyus3KnXs4Ez [link added]

Sending the wrong amount means I won’t know it’s you who paid.

You have 7 days from receipt of this email to send the BTC [bitcoins]. If you need help locating a place to purchase BTC, you can start here…..

The individual who received that extortion attempt — an AshleyMadison user who agreed to speak about the attack on condition that only his first name be used — said he’s “loosely concerned” about future extortion attacks, but not especially this one in particular.

“If I put myself in [the extortionist’s] shoes, the likelihood of them disclosing stuff doesn’t increase their chance of getting money,” said Mac. “I just not going to respond.” Continue reading →

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