Krebs on Security

Critical Update for Adobe Reader & Acrobat

September 17, 2014

Adobe has released a security update for its Acrobat and PDF Reader products that fixes at least eight critical vulnerabilities in Mac and Windows versions of the software. If you use either of these programs, please take a minute to update now.

Users can manually check for updates by choosing Help > Check for Updates. Adobe Reader users on Windows also can get the latest version here; Mac users, here.

Adobe said it is not aware of exploits or active attacks in the wild against any of the flaws addressed in this update. More information about the patch is available at this link.

For those seeking a lightweight, free alternative to Adobe Reader, check out Sumatra PDF. Foxit Reader is another popular alternative, although it seems to have become less lightweight in recent years.

Breach at Goodwill Vendor Lasted 18 Months

September 16, 2014

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C&K Systems Inc., a third-party payment vendor blamed for a credit and debit card breach at more than 330 Goodwill locations nationwide, disclosed this week that the intrusion lasted more than 18 months and has impacted at least two other organizations.

On July 21, 2014, this site broke the news that multiple banks were reporting indications that Goodwill Industries had suffered an apparent breach that led to the theft of customer credit and debit card data. Goodwill later confirmed that the breach impacted a portion of its stores, but blamed the incident on an unnamed “third-party vendor.”

Last week, KrebsOnSecurity obtained some internal talking points apparently sent by Goodwill to prepare its member organizations to respond to any calls from the news media about the incident. Those talking points identified the breached third-party vendor as C&K Systems, a retail point-of-sale operator based in Murrells Inlet, S.C.

In response to inquiries from this reporter, C&K released a statement acknowledging that it was informed on July 30 by “an independent security analyst” that its “hosted managed services environment may have experienced unauthorized access.” The company says it then hired an independent cyber investigative team and alerted law enforcement about the incident.

C&K says the investigation determined malicious hackers had access to its systems “intermittently” between Feb. 10, 2013 and Aug. 14, 2014, and that the intrusion led to the the installation of “highly specialized point of sale (POS) infostealer.rawpos malware variant that was undetectable by our security software systems until Sept. 5, 2014,” [link added].

Their statement continues:

“This unauthorized access currently is known to have affected only three (3) customers of C&K, including Goodwill Industries International. While many payment cards may have been compromised, the number of these cards of which we are informed have been used fraudulently is currently less than 25.”

C&K System’s full statement is posted here. Continue reading →

LinkedIn Feature Exposes Email Addresses

September 15, 2014

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One of the risks of using social media networks is having information you intend to share with only a handful of friends be made available to everyone. Sometimes that over-sharing happens because friends betray your trust, but more worrisome are the cases in which a social media platform itself exposes your data in the name of marketing.

LinkedIn has built much of its considerable worth on the age-old maxim that “it’s all about who you know.” As a LinkedIn user, you can directly connect with those you attest to knowing professionally or personally, but also you can ask to be introduced to someone you’d like to meet by sending a request through someone who bridges your separate social networks. Celebrities, executives or any other LinkedIn users who wish to avoid unsolicited contact requests may do so by selecting an option that forces the requesting party to supply the personal email address of the intended recipient.

LinkedIn’s entire social fabric begins to unravel if any user can directly connect to any other user, regardless of whether or how their social or professional circles overlap. Unfortunately for LinkedIn (and its users who wish to have their email addresses kept private), this is the exact risk introduced by the company’s built-in efforts to expand the social network’s user base.

According to researchers at the Seattle, Wash.-based firm Rhino Security Labs, at the crux of the issue is LinkedIn’s penchant for making sure you’re as connected as you possibly can be. When you sign up for a new account, for example, the service asks if you’d like to check your contacts lists at other online services (such as Gmail, Yahoo, Hotmail, etc.). The service does this so that you can connect with any email contacts that are already on LinkedIn, and so that LinkedIn can send invitations to your contacts who aren’t already users.

LinkedIn assumes that if an email address is in your contacts list, that you must already know this person. But what if your entire reason for signing up with LinkedIn is to discover the private email addresses of famous people? All you’d need to do is populate your email account’s contacts list with hundreds of permutations of famous peoples’ names — including combinations of last names, first names and initials — in front of @gmail.com, @yahoo.com, @hotmail.com, etc. With any luck and some imagination, you may well be on your way to an A-list LinkedIn friends list (or a fantastic set of addresses for spear-phishing, stalking, etc.).

LinkedIn lets you know which of your contacts aren’t members.

When you import your list of contacts from a third-party service or from a stand-alone file, LinkedIn will show you any profiles that match addresses in your contacts list. More significantly, LinkedIn helpfully tells you which email addresses in your contacts lists are not LinkedIn users.

It’s that last step that’s key to finding the email address of the targeted user to whom LinkedIn has just sent a connection request on your behalf. The service doesn’t explicitly tell you that person’s email address, but by comparing your email account’s contact list to the list of addresses that LinkedIn says don’t belong to any users, you can quickly figure out which address(es) on the contacts list correspond to the user(s) you’re trying to find.

Rhino Security founders Benjamin Caudill and Bryan Seely have a recent history of revealing how trust relationships between and among online services can be abused to expose or divert potentially sensitive information. Last month, the two researchers detailed how they were able to de-anonymize posts to Secret, an app-driven online service that allows people to share messages anonymously within their circle of friends, friends of friends, and publicly. In February, Seely more famously demonstrated how to use Google Maps to intercept FBI and Secret Service phone calls.

This time around, the researchers picked on Dallas Mavericks owner Mark Cuban to prove their point with LinkedIn. Using their low-tech hack, the duo was able to locate the Webmail address Cuban had used to sign up for LinkedIn. Seely said they found success in locating the email addresses of other celebrities using the same method about nine times out ten. Continue reading →

Critical Fixes for Adobe, Microsoft Software

September 9, 2014

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Adobe today released updates to fix at least a dozen critical security problems in its Flash Player and AIR software. Separately, Microsoft pushed four update bundles to address at least 42 vulnerabilities in Windows, Internet Explorer, Lync and .NET Framework. If you use any of these, it’s time to update! Continue reading →

In Wake of Confirmed Breach at Home Depot, Banks See Spike in PIN Debit Card Fraud

September 8, 2014

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Nearly a week after this blog first reported signs that Home Depot was battling a major security incident, the company has acknowledged that it suffered a credit and debit card breach involving its U.S. and Canadian stores dating back to April 2014. Home Depot was quick to assure customers and banks that no debit card PIN data was compromised in the break-in. Nevertheless, multiple financial institutions contacted by this publication are reporting a steep increase over the past few days in fraudulent ATM withdrawals on customer accounts.

The card data for sale in the underground that was stolen from Home Depot shoppers allows thieves to create counterfeit copies of debit and credit cards that can be used to purchase merchandise in big box stores. But if the crooks who buy stolen debit cards also are able to change the PIN on those accounts, the fabricated debit cards can then be used to withdraw cash from ATMs.

Experts say the thieves who are perpetrating the debit card fraud are capitalizing on a glut of card information stolen from Home Depot customers and being sold in cybercrime shops online. Those same crooks also are taking advantage of weak authentication methods in the automated phone systems that many banks use to allow customers to reset the PINs on their cards.

Here’s the critical part: The card data stolen from Home Depot customers and now for sale on the crime shop Rescator[dot]cc includes both the information needed to fabricate counterfeit cards as well as the legitimate cardholder’s full name and the city, state and ZIP of the Home Depot store from which the card was stolen (presumably by malware installed on some part of the retailer’s network, and probably on each point-of-sale device).

This is especially helpful for fraudsters since most Home Depot transactions are likely to occur in the same or nearby ZIP code as the cardholder. The ZIP code data of the store is important because it allows the bad guys to quickly and more accurately locate the Social Security number and date of birth of cardholders using criminal services in the underground that sell this information.

Why do the thieves need Social Security and date of birth information? Countless banks in the United States let customers change their PINs with a simple telephone call, using an automated call-in system known as a Voice Response Unit (VRU). A large number of these VRU systems allow the caller to change their PIN provided they pass three out of five security checks. One is that the system checks to see if the call is coming from a phone number on file for that customer. It also requests the following four pieces of information:

-the 3-digit code (known as a card verification value or CVV/CV2) printed on the back of the debit card;
-the card’s expiration date;
-the customer’s date of birth;
-the last four digits of the customer’s Social Security number.

On Thursday, I spoke with a fraud fighter at a bank in New England that experienced more than $25,000 in PIN debit fraud at ATMs in Canada. The bank employee said thieves were able to change the PINs on the cards using the bank’s automated VRU system. In this attack, the fraudsters were calling from disposable, prepaid Magic Jack telephone numbers, and they did not have the Cv2 for each card. But they were able to supply the other three data points.

KrebsOnSecurity also heard from an employee at a much larger bank on the West Coast that lost more than $300,000 in two hours today to PIN fraud on multiple debit cards that had all been used recently at Home Depot. The manager said the bad guys called the customer service folks at the bank and provided the last four of each cardholder’s Social Security number, date of birth, and the expiration date on the card. And, as with the bank in New England, that was enough information for the bank to reset the customer’s PIN.

The fraud manager said the scammers in this case also told the customer service people they were traveling in Italy, which made two things possible: It raised the withdrawal limits on the debit cards and allowed thieves to withdraw $300,000 in cash from Italian ATMs in the span of less than 120 minutes. Continue reading →

Home Depot Hit By Same Malware as Target

September 7, 2014

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The apparent credit and debit card breach uncovered last week at Home Depot was aided in part by a new variant of the malicious software program that stole card account data from cash registers at Target last December, according to sources close to the investigation.

Photo: Nicholas Eckhart

On Tuesday, KrebsOnSecurity broke the news that Home Depot was working with law enforcement to investigate “unusual activity” after multiple banks said they’d traced a pattern of card fraud back to debit and credit cards that had all been used at Home Depot locations since May of this year.

A source close to the investigation told this author that an analysis revealed at least some of Home Depot’s store registers had been infected with a new variant of “BlackPOS” (a.k.a. “Kaptoxa”), a malware strain designed to siphon data from cards when they are swiped at infected point-of-sale systems running Microsoft Windows.

The information on the malware adds another indicator that those responsible for the as-yet unconfirmed breach at Home Depot also were involved in the December 2013 attack on Target that exposed 40 million customer debit and credit card accounts. BlackPOS also was found on point-of-sale systems at Target last year. What’s more, cards apparently stolen from Home Depot shoppers first turned up for sale on Rescator[dot]cc, the same underground cybercrime shop that sold millions of cards stolen in the Target attack.

Clues buried within this newer version of BlackPOS support the theory put forth by multiple banks that the Home Depot breach may involve compromised store transactions going back at least several months. In addition, the cybercrime shop Rescator over the past few days pushed out nine more large batches of stolen cards onto his shop, all under the same “American Sanctions” label assigned to the first two batches of cards that originally tipped off banks to a pattern of card fraud that traced back to Home Depot. Likewise, the cards lifted from Target were sold in several dozen batches released over a period of three months on Rescator’s shop.

The cybercrime shop Rescator[dot]cc pushed out nine new batches of cards from the same “American Sanctions” base of cards that banks traced back to Home Depot.

POWERFUL ENEMIES

The tip from a source about BlackPOS infections found at Home Depot comes amid reports from several security firms about the discovery of a new version of BlackPOS. On Aug. 29, Trend Micro published a blog post stating that it had identified a brand new variant of BlackPOS in the wild that was targeting retail accounts. Trend said the updated version, which it first spotted on Aug. 22, sports a few notable new features, including an enhanced capability to capture card data from the physical memory of infected point-of-sale devices. Trend said the new version also has a feature that disguises the malware as a component of the antivirus product running on the system.

Contents of the new BlackPOS component responsible for exfiltrating stolen cards from the network. Source: Trend Micro.

Continue reading →

Dread Pirate Sunk By Leaky CAPTCHA

September 6, 2014

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Ever since October 2013, when the FBI took down the online black market and drug bazaar known as the Silk Road, privacy activists and security experts have traded conspiracy theories about how the U.S. government managed to discover the geographic location of the Silk Road Web servers. Those systems were supposed to be obscured behind the anonymity service Tor, but as court documents released Friday explain, that wasn’t entirely true: Turns out, the login page for the Silk Road employed an anti-abuse CAPTCHA service that pulled content from the open Internet, thus leaking the site’s true location.

Tor helps users disguise their identity by bouncing their traffic between different Tor servers, and by encrypting that traffic at every hop along the way. The Silk Road, like many sites that host illicit activity, relied on a feature of Tor known as “hidden services.” This feature allows anyone to offer a Web server without revealing the true Internet address to the site’s users.

That is, if you do it correctly, which involves making sure you aren’t mixing content from the regular open Internet into the fabric of a site protected by Tor. But according to federal investigators, Ross W. Ulbricht — a.k.a. the “Dread Pirate Roberts,” the 30-year-old arrested last year and charged with running the Silk Road — made this exact mistake. Continue reading →

Data: Nearly All U.S. Home Depot Stores Hit

September 3, 2014

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New data gathered from the cybercrime underground suggests that the apparent credit and debit card breach at Home Depot involves nearly all of the company’s stores across the nation.

Evidence that a major U.S. retailer had been hacked and was leaking card data first surfaced Tuesday on the cybercrime store rescator[dot]cc, the shop that was principally responsible for selling cards stolen in the Target, Sally Beauty, P.F. Chang’s and Harbor Freight credit card breaches.

As with cards put up for sale in the wake of those breaches, Rescator’s shop lists each card according to the city, state and ZIP code of the store from which each card was stolen. See this story for examples of this dynamic in the case of Sally Beauty, and this piece that features the same analysis on the stolen card data from the Target breach.

Stolen credit cards for sale on Rescator’s site index each card by the city, state and ZIP of the retail store from which each card was stolen.

The ZIP code data allows crooks who buy these cards to create counterfeit copies of the credit and debit cards, and use them to buy gift cards and high-priced merchandise from big box retail stores. This information is extremely valuable to the crooks who are purchasing the stolen cards, for one simple reason: Banks will often block in-store card transactions on purchases that occur outside of the legitimate cardholder’s geographic region (particularly in the wake of a major breach).

Thus, experienced crooks prefer to purchase cards that were stolen from stores near them, because they know that using the cards for fraudulent purchases in the same geographic area as the legitimate cardholder is less likely to trigger alerts about suspicious transactions — alerts that could render the stolen card data worthless for the thieves.

This morning, KrebsOnSecurity pulled down all of the unique ZIP codes in the card data currently for sale from the two batches of cards that at least four banks have now mapped back to previous transactions at Home Depot. KrebsOnSecurity also obtained a commercial marketing list showing the location and ZIP code of every Home Depot store across the country.

Here’s the kicker: A comparison of the ZIP code data between the unique ZIPs represented on Rescator’s site, and those of the Home Depot stores shows a staggering 99.4 percent overlap.

Home Depot has not yet said for certain whether it has in fact experienced a store-wide card breach; rather, the most that the company is saying so far is that it is investigating “unusual activity” and that it is working with law enforcement on an investigation. Here is the page that Home Depot has set up for further notices about this investigation.

I double checked the data with several sources, including with Nicholas Weaver, a researcher at the International Computer Science Institute (ICSI) and at the University California, Berkeley. Weaver said the data suggests a very strong correlation.

“A 99+ percent overlap in ZIP codes strongly suggests that this source is from Home Depot,” Weaver said. Continue reading →

Banks: Credit Card Breach at Home Depot

September 2, 2014

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Multiple banks say they are seeing evidence that Home Depot stores may be the source of a massive new batch of stolen credit and debit cards that went on sale this morning in the cybercrime underground. Home Depot says that it is working with banks and law enforcement agencies to investigate reports of suspicious activity.

Contacted by this reporter about information shared from several financial institutions, Home Depot spokesperson Paula Drake confirmed that the company is investigating.

“I can confirm we are looking into some unusual activity and we are working with our banking partners and law enforcement to investigate,” Drake said, reading from a prepared statement. “Protecting our customers’ information is something we take extremely seriously, and we are aggressively gathering facts at this point while working to protect customers. If we confirm that a breach has occurred, we will make sure customers are notified immediately. Right now, for security reasons, it would be inappropriate for us to speculate further – but we will provide further information as soon as possible.”

There are signs that the perpetrators of this apparent breach may be the same group of Russian and Ukrainian hackers responsible for the data breaches at Target, Sally Beauty and P.F. Chang’s, among others. The banks contacted by this reporter all purchased their customers’ cards from the same underground store — rescator[dot]cc — which on Sept. 2 moved two massive new batches of stolen cards onto the market.

A massive new batch of cards labeled “American Sanctions” and “European Sanctions” went on sale Tuesday, Sept. 2, 2014.

In what can only be interpreted as intended retribution for U.S. and European sanctions against Russia for its aggressive actions in Ukraine, this crime shop has named its newest batch of cards “American Sanctions.” Stolen cards issued by European banks that were used in compromised US store locations are being sold under a new batch of cards labled “European Sanctions.” Continue reading →

Fun With Funny Money

September 1, 2014

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Readers or “fans” of this blog have sent some pretty crazy stuff to my front door over the past few years, including a gram of heroin, a giant bag of feces, an enormous cross-shaped funeral arrangement, and a heavily armed police force. Last week, someone sent me a far less menacing package: an envelope full of cash. Granted, all of the cash turned out to be counterfeit money, but hey it’s the thought that counts, right?

Counterfeit $100s and $50s

This latest “donation” to Krebs On Security arrived via USPS Priority Mail, just days after I’d written about counterfeit cash sold online by a shadowy figure known only as “MrMouse.” These counterfeits had previously been offered on “dark web” — sites only accessible using special software such as Tor — but I wrote about MrMouse’s funny money because he’d started selling it openly on Reddit, as well as on a half-dozen hacker forums that are quite reachable on the regular Internet.

Sure enough, the package contained the minimum order that MrMouse allows: $500, split up into four fake $100s and two phony $50 bills — all with different serial numbers. I have no idea who sent the bogus bills; perhaps it was MrMouse himself, hoping I’d write a review of his offering. After all, since my story about his service was picked up by multiple media outlets, he’s changed his sales thread on several crime forums to read, “As seen on KrebsOnSecurity, Business Insider and Ars Technica…”

Anyhow, it’s not every day that I get a firsthand look at counterfeit cash, so for better for worse, I decided it would be a shame not to write about it. Since I was preparing to turn the entire package over to the local cops, I was careful to handle the cash sparingly and only with gloves. At first glance, the cash does look and feel like the real thing. Closer inspection, however, reveals that these bills are fakes.

In the video below, I run the fake bills through two basic tests designed to determine the authenticity of U.S. currency: The counterfeit pen test, and ultraviolet light. As we’ll see in the video, the $50 bills shipped in this package sort of failed the pen test (the fake $100 more or less passed). However, both the $50s and $100s completely flopped on the ultraviolet test. It’s too bad more businesses don’t check bills with a cheapo ultraviolet light: the pen test apparently can be defeated easily (by using acid-free paper or by bleaching real bills and using them as a starting point).

Let’s check out the bogus Benjamins. In the image below, we can see a pretty big difference in the watermarks on both bills. The legitimate $100 bill — shown at the bottom of the picture — has a very defined image of Benjamin Franklin as a watermark. In contrast, the fake $100 up top has a much less detailed watermark. Still, without comparing the fake and the real $100 side by side, this deficiency probably would be difficult to spot for the untrained eye.

The fake $100 (top) has a much less defined Ben Franklin for a watermark. The color difference between these two bills is negligible, but the legitimate $100 appears darker here because it was closer to the light source behind the bills when this photo was taken.

Continue reading →

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