Latest Warnings

Mar 18

Checked Your Credit Since the Equifax Hack?

A recent consumer survey suggests that half of all Americans still haven’t checked their credit report since the Equifax breach last year exposed the Social Security numbers, dates of birth, addresses and other personal information on nearly 150 million people. If you’re in that fifty percent, please make an effort to remedy that soon.

Credit reports from the three major bureaus — Equifax, Experian and TransUnion — can be obtained online for free at — the only Web site mandated by Congress to serve each American a free credit report every year. is run by a Florida-based company, but its data is supplied by the major credit bureaus, which struggled mightily to meet consumer demand for free credit reports in the immediate aftermath of the Equifax breach. Personally, I was unable to order a credit report for either me or my wife even two weeks after the Equifax breach went public: The site just kept returning errors and telling us to request the reports in writing via the U.S. Mail.

Based on thousands of comments left here in the days following the Equifax breach disclosure, I suspect many readers experienced the same but forgot to come back and try again. If this describes you, please take a moment this week to order your report(s) (and perhaps your spouse’s) and see if anything looks amiss. If you spot an error or something suspicious, contact the bureau that produced the report to correct the record immediately.

Of course, keeping on top of your credit report requires discipline, and if you’re not taking advantage of all three free reports each year you need to get a plan. My strategy is to put a reminder on our calendar to order a new report every four months or so, each time from a different credit bureau. Continue reading →

Mar 18

Look-Alike Domains and Visual Confusion

How good are you at telling the difference between domain names you know and trust and impostor or look-alike domains? The answer may depend on how familiar you are with the nuances of internationalized domain names (IDNs), as well as which browser or Web application you’re using.

For example, how does your browser interpret the following domain? I’ll give you a hint: Despite appearances, it is most certainly not the actual domain for software firm CA Technologies (formerly Computer Associates Intl Inc.), which owns the original domain name:


Go ahead and click on the link above or cut-and-paste it into a browser address bar. If you’re using Google Chrome, Apple’s Safari, or some recent version of Microsoft‘s Internet Explorer or Edge browsers, you should notice that the address converts to “” This is called “punycode,” and it allows browsers to render domains with non-Latin alphabets like Cyrillic and Ukrainian.

Below is what it looks like in Edge on Windows 10; Google Chrome renders it much the same way. Notice what’s in the address bar (ignore the “fake site” and “Welcome to…” text, which was added as a courtesy by the person who registered this domain):

The domain https://www.са.com/ as rendered by Microsoft Edge on Windows 10. The rest of the text in the image (beginning with “Welcome to a site…”) was added by the person who registered this test domain, not the browser.

IE, Edge, Chrome and Safari all will convert https://www.са.com/ into its punycode output (, in part to warn visitors about any confusion over look-alike domains registered in other languages. But if you load that domain in Mozilla Firefox and look at the address bar, you’ll notice there’s no warning of possible danger ahead. It just looks like it’s loading the real

What the fake domain looks like when loaded in Mozilla Firefox. A browser certificate ordered from Comodo allows it to include the green lock (https://) in the address bar, adding legitimacy to the look-alike domain. The rest of the text in the image (beginning with “Welcome to a site…”) was added by the person who registered this test domain, not the browser. Click to enlarge.

The domain “” pictured in the first screenshot above is punycode for the Ukrainian letters for “s” (which is represented by the character “c” in Russian and Ukrainian), as well as an identical Ukrainian “a”.

It was registered by Alex Holden, founder of Milwaukee, Wis.-based Hold Security Inc. Holden’s been experimenting with how the different browsers handle punycodes in the browser and via email. Holden grew up in what was then the Soviet Union and speaks both Russian and Ukrainian, and he’s been playing with Cyrillic letters to spell English words in domain names.

Letters like A and O look exactly the same and the only difference is their Unicode value. There are more than 136,000 Unicode characters used to represent letters and symbols in 139 modern and historic scripts, so there’s a ton of room for look-alike or malicious/fake domains.

For example, “a” in Latin is the Unicode value “0061” and in Cyrillic is “0430.”  To a human, the graphical representation for both looks the same, but for a computer there is a huge difference. Internationalized domain names (IDNs) allow domain names to be registered in non-Latin letters (RFC 3492), provided the domain is all in the same language; trying to mix two different IDNs in the same name causes the domain registries to reject the registration attempt.

So, in the Cyrillic alphabet (Russian/Ukrainian), we can spell АТТ, УАНОО, ХВОХ, and so on. As you can imagine, the potential opportunity for impersonation and abuse are great with IDNs. Here’s a snippet from a larger chart Holden put together showing some of the more common ways that IDNs can be made to look like established, recognizable domains:

Image: Hold Security.

Holden also was able to register a valid SSL encryption certificate for https://www.са.com from, which would only add legitimacy to the domain were it to be used in phishing attacks against CA customers by bad guys, for example. Continue reading →

Mar 18

Financial Cyber Threat Sharing Group Phished

The Financial Services Information Sharing and Analysis Center (FS-ISAC), an industry forum for sharing data about critical cybersecurity threats facing the banking and finance industries, said today that a successful phishing attack on one of its employees was used to launch additional phishing attacks against FS-ISAC members.

The fallout from the back-to-back phishing attacks appears to have been limited and contained, as many FS-ISAC members who received the phishing attack quickly detected and reported it as suspicious. But the incident is a good reminder to be on your guard, remember that anyone can get phished, and that most phishing attacks succeed by abusing the sense of trust already established between the sender and recipient.

The confidential alert FS-ISAC sent to members about a successful phishing attack that spawned phishing emails coming from the FS-ISAC.

Notice of the phishing incident came in an alert FS-ISAC shared with its members today and obtained by KrebsOnSecurity. It describes an incident on Feb. 28 in which an FS-ISAC employee “clicked on a phishing email, compromising that employee’s login credentials. Using the credentials, a threat actor created an email with a PDF that had a link to a credential harvesting site and was then sent from the employee’s email account to select members, affiliates and employees.”

The alert said while FS-ISAC was already planning and implementing a multi-factor authentication (MFA) solution across all of its email platforms, “unfortunately, this incident happened to an employee that was not yet set up for MFA. We are accelerating our MFA solution across all FS-ISAC assets.”

The FS-ISAC also said it upgraded its Office 365 email version to provide “additional visibility and security.”

In an interview with KrebsOnSecurity, FS-ISAC President and CEO Bill Nelson said his organization has grown significantly in new staff over the past few years to more than 75 people now, including Greg Temm, the FS-ISAC’s chief information risk officer.

“To say I’m disappointed this got through is an understatement,” Nelson said. “We need to accelerate MFA extremely quickly for all of our assets.” Continue reading →

Feb 18

How to Fight Mobile Number Port-out Scams

T-Mobile, AT&T and other mobile carriers are reminding customers to take advantage of free services that can block identity thieves from easily “porting” your mobile number out to another provider, which allows crooks to intercept your calls and messages while your phone goes dark. Tips for minimizing the risk of number porting fraud are available below for customers of all four major mobile providers, including Sprint and Verizon.

Unauthorized mobile phone number porting is not a new problem, but T-Mobile said it began alerting customers about it earlier this month because the company has seen a recent uptick in fraudulent requests to have customer phone numbers ported over to another mobile provider’s network.

“We have been alerting customers via SMS that our industry is experiencing a phone number port out scam that could impact them,” T-Mobile said in a written statement. “We have been encouraging them to add a port validation feature, if they’ve not already done so.”

Crooks typically use phony number porting requests when they have already stolen the password for a customer account (either for the mobile provider’s network or for another site), and wish to intercept the one-time password that many companies send to the mobile device to perform two-factor authentication.

Porting a number to a new provider shuts off the phone of the original user, and forwards all calls to the new device. Once in control of the mobile number, thieves can request any second factor that is sent to the newly activated device, such as a one-time code sent via text message or or an automated call that reads the one-time code aloud.

In these cases, the fraudsters can call a customer service specialist at a mobile provider and pose as the target, providing the mark’s static identifiers like name, date of birth, social security number and other information. Often this is enough to have a target’s calls temporarily forwarded to another number, or ported to a different provider’s network.

Port out fraud has been an industry problem for a long time, but recently we’ve seen an uptick in this illegal activity,” T-Mobile said.  “We’re not providing specific metrics, but it’s been enough that we felt it was important to encourage customers to add extra security features to their accounts.”

In a blog post published Tuesday, AT&T said bad guys sometimes use illegal porting to steal your phone number, transfer the number to a device they control and intercept text authentication messages from your bank, credit card issuer or other companies.

“You may not know this has happened until you notice your mobile device has lost service,” reads a post by Brian Rexroad, VP of security relations at AT&T. “Then, you may notice loss of access to important accounts as the attacker changes passwords, steals your money, and gains access to other pieces of your personal information.”

Rexroad says in some cases the thieves just walk into an AT&T store and present a fake ID and your personal information, requesting to switch carriers. Porting allows customers to take their phone number with them when they change phone carriers.

The law requires carriers to provide this number porting feature, but there are ways to reduce the risk of this happening to you. Continue reading →

Feb 18

Attackers Exploiting Unpatched Flaw in Flash

Adobe warned on Thursday that attackers are exploiting a previously unknown security hole in its Flash Player software to break into Microsoft Windows computers. Adobe said it plans to issue a fix for the flaw in the next few days, but now might be a good time to check your exposure to this still-ubiquitous program and harden your defenses.

Adobe said a critical vulnerability (CVE-2018-4878) exists in Adobe Flash Player and earlier versions. Successful exploitation could allow an attacker to take control of the affected system.

The software company warns that an exploit for the flaw is being used in the wild, and that so far the attacks leverage Microsoft Office documents with embedded malicious Flash content. Adobe said it plans to address this vulnerability in a release planned for the week of February 5.

According to Adobe’s advisory, beginning with Flash Player 27, administrators have the ability to change Flash Player’s behavior when running on Internet Explorer on Windows 7 and below by prompting the user before playing Flash content. A guide on how to do that is here (PDF). Administrators may also consider implementing Protected View for Office. Protected View opens a file marked as potentially unsafe in Read-only mode.

Continue reading →

Jan 18

First ‘Jackpotting’ Attacks Hit U.S. ATMs

ATM “jackpotting” — a sophisticated crime in which thieves install malicious software and/or hardware at ATMs that forces the machines to spit out huge volumes of cash on demand — has long been a threat for banks in Europe and Asia, yet these attacks somehow have eluded U.S. ATM operators. But all that changed this week after the U.S. Secret Service quietly began warning financial institutions that jackpotting attacks have now been spotted targeting cash machines here in the United States.

To carry out a jackpotting attack, thieves first must gain physical access to the cash machine. From there they can use malware or specialized electronics — often a combination of both — to control the operations of the ATM.

A keyboard attached to the ATM port. Image: FireEye

On Jan. 21, 2018, KrebsOnSecurity began hearing rumblings about jackpotting attacks, also known as “logical attacks,” hitting U.S. ATM operators. I quickly reached out to ATM giant NCR Corp. to see if they’d heard anything. NCR said at the time it had received unconfirmed reports, but nothing solid yet.

On Jan. 26, NCR sent an advisory to its customers saying it had received reports from the Secret Service and other sources about jackpotting attacks against ATMs in the United States.

“While at present these appear focused on non-NCR ATMs, logical attacks are an industry-wide issue,” the NCR alert reads. “This represents the first confirmed cases of losses due to logical attacks in the US. This should be treated as a call to action to take appropriate steps to protect their ATMs against these forms of attack and mitigate any consequences.”

The NCR memo does not mention the type of jackpotting malware used against U.S. ATMs. But a source close to the matter said the Secret Service is warning that organized criminal gangs have been attacking stand-alone ATMs in the United States using “Ploutus.D,” an advanced strain of jackpotting malware first spotted in 2013.

According to that source — who asked to remain anonymous because he was not authorized to speak on the record — the Secret Service has received credible information that crooks are activating so-called “cash out crews” to attack front-loading ATMs manufactured by ATM vendor Diebold Nixdorf.

The source said the Secret Service is warning that thieves appear to be targeting Opteva 500 and 700 series Dielbold ATMs using the Ploutus.D malware in a series of coordinated attacks over the past 10 days, and that there is evidence that further attacks are being planned across the country.

“The targeted stand-alone ATMs are routinely located in pharmacies, big box retailers, and drive-thru ATMs,” reads a confidential Secret Service alert sent to multiple financial institutions and obtained by KrebsOnSecurity. “During previous attacks, fraudsters dressed as ATM technicians and attached a laptop computer with a mirror image of the ATMs operating system along with a mobile device to the targeted ATM.

Reached for comment, Diebold shared an alert it sent to customers Friday warning of potential jackpotting attacks in the United States. Diebold’s alert confirms the attacks so far appear to be targeting front-loaded Opteva cash machines.

“As in Mexico last year, the attack mode involves a series of different steps to overcome security mechanism and the authorization process for setting the communication with the [cash] dispenser,” the Diebold security alert reads. A copy of the entire Diebold alert, complete with advice on how to mitigate these attacks, is available here (PDF). Continue reading →

Jan 18

Bitcoin Blackmail by Snail Mail Preys on Those with Guilty Conscience

KrebsOnSecurity heard from a reader whose friend recently received a remarkably customized extortion letter via snail mail that threatened to tell the recipient’s wife about his supposed extramarital affairs unless he paid $3,600 in bitcoin. The friend said he had nothing to hide and suspects this is part of a random but well-crafted campaign to prey on men who may have a guilty conscience.

The letter addressed the recipient by his first name and hometown throughout, and claimed to have evidence of the supposed dalliances.

“You don’t know me personally and nobody hired me to look into you,” the letter begins. “Nor did I go out looking to burn you. It is just your bad luck that I stumbled across your misadventures while working on a job around Bellevue.”

The missive continues:

“I then put in more time than I probably should have looking into your life. Frankly, I am ready to forget all about you and let you get on with your life. And I am going to give you two options that will accomplish that very thing. These two options are to either ignore this letter, or simply pay me $3,600. Let’s examine those two options in more detail.”

The letter goes on to say that option 1 (ignoring the threat) means the author will send copies of his alleged evidence to the man’s wife and to her friends and family if he does not receive payment within 12 days of the letter’s post marked date.

“So [name omitted], even if you decide to come clean with your wife, it won’t protect her from the humiliation she will feel when her friends and family find out your sordid details from me,” the extortionist wrote. Continue reading →

Dec 17

Buyers Beware of Tampered Gift Cards

Prepaid gift cards make popular presents and no-brainer stocking stuffers, but before you purchase one be on the lookout for signs that someone may have tampered with it. A perennial scam that picks up around the holidays involves thieves who pull back and then replace the decals that obscure the card’s redemption code, allowing them to redeem or transfer the card’s balance online after the card is purchased by an unwitting customer.

Last week KrebsOnSecurity heard from Colorado reader Flint Gatrell, who reached out after finding that a bunch of Sam’s Club gift cards he pulled off the display rack at Wal-Mart showed signs of compromise. The redemption code was obscured by a watermarked sticker that is supposed to make it obvious if it has been tampered with, and many of the cards he looked at clearly had stickers that had been peeled back and then replaced.

“I just identified five fraudulent gift cards on display at my local Wal-Mart,” Gatrell said. “They each had their stickers covering their codes peeled back and replaced. I can only guess that the thieves call the service number to monitor the balances, and try to consume them before the victims can.  I’m just glad I thought to check!”

In the picture below, Gatrell is holding up three of the Sam’s Club cards. The top two showed signs of tampering, but the one on the bottom appeared to be intact.

The top two gift cards show signs that someone previously peeled back the protective sticker covering the redemption code. Image: Flint Gatrell.

Continue reading →

Dec 17

Phishers Are Upping Their Game. So Should You.

Not long ago, phishing attacks were fairly easy for the average Internet user to spot: Full of grammatical and spelling errors, and linking to phony bank or email logins at unencrypted (http:// vs. https://) Web pages. Increasingly, however, phishers are upping their game, polishing their copy and hosting scam pages over https:// connections — complete with the green lock icon in the browser address bar to make the fake sites appear more legitimate.

A brand new (and live) PayPal phishing page that uses SSL (https://) to appear more legitimate.

According to stats released this week by anti-phishing firm PhishLabs, nearly 25 percent of all phishing sites in the third quarter of this year were hosted on HTTPS domains — almost double the percentage seen in the previous quarter.

“A year ago, less than three percent of phish were hosted on websites using SSL certificates,” wrote Crane Hassold, the company’s threat intelligence manager. “Two years ago, this figure was less than one percent.”

A currently live Facebook phishing page that uses https.

As shown in the examples above (which KrebsOnSecurity found in just a few minutes of searching via phish site reporting service, the most successful phishing sites tend to include not only their own SSL certificates but also a portion of the phished domain in the fake address.

Why are phishers more aggressively adopting HTTPS Web sites? Traditionally, many phishing pages are hosted on hacked, legitimate Web sites, in which case the attackers can leverage both the site’s good reputation and its SSL certificate.

Yet this, too, is changing, says PhishLabs’ Hassold.

“An analysis of Q3 HTTPS phishing attacks against PayPal and Apple, the two primary targets of these attacks, indicates that nearly three-quarters of HTTPS phishing sites targeting them were hosted on maliciously-registered domains rather than compromised websites, which is substantially higher than the overall global rate,” he wrote. “Based on data from 2016, slightly less than half of all phishing sites were hosted on domains registered by a threat actor.”

Hassold posits that more phishers are moving to HTTPS because it helps increase the likelihood that users will trust that the site is legitimate. After all, your average Internet user has been taught for years to simply “look for the lock icon” in the browser address bar as assurance that a site is safe.

Perhaps this once was useful advice, but if so its reliability has waned over the years. In November, PhishLabs conducted a poll to see how many people actually knew the meaning of the green padlock that is associated with HTTPS websites.

“More than 80% of the respondents believed the green lock indicated that a website was either legitimate and/or safe, neither of which is true,” he wrote. Continue reading →

Aug 16

Visa Alert and Update on the Oracle Breach

Credit card industry giant Visa on Friday issued a security alert warning companies using point-of-sale devices made by Oracle‘s MICROS retail unit to double-check the machines for malicious software or unusual network activity, and to change passwords on the devices. Visa also published a list of Internet addresses that may have been involved in the Oracle breach and are thought to be closely tied to an Eastern European organized cybercrime gang.


The Visa alert is the first substantive document that tries to help explain what malware and which malefactors might have hit Oracle — and by extension many of Oracle’s customers — since KrebsOnSecurity broke news of the breach on Aug. 8. That story cited sources close to the investigation saying hackers had broken into hundreds of servers at Oracle’s retail division, and had completely compromised Oracle’s main online support portal for MICROS customers.

MICROS is among the top three point-of-sale vendors globally. Oracle’s MICROS division sells point-of-sale systems used at more than 330,000 cash registers worldwide. When Oracle bought MICROS in 2014, the company said MICROS’s systems were deployed at some 200,000+ food and beverage outlets, 100,000+ retail sites, and more than 30,000 hotels.

In short, tens of millions of credit cards are swiped at MICROS terminals monthly, and a breach involving the theft of credentials that might have granted remote access to even just a small percentage of those systems is potentially a big and costly problem for all involved.

So far, however, most MICROS customers are left scratching their heads for answers. A frequently asked questions bulletin (PDF) Oracle also released last Monday held little useful information. Oracle issued the same cryptic response to everyone who asked for particulars about how far the breach extended. “Oracle has detected and addressed malicious code in certain legacy MICROS systems.”

Oracle also urged MICROS customers to change their passwords, and said “we also recommend that you change the password for any account that was used by a MICROS representative to access your on-premises systems.”

One of two documents Oracle sent to MICROS customers and the sum total of information the company has released so far about the breach.

One of two documents Oracle sent to MICROS customers and the sum total of information the company has released so far about the breach.

Some technology and fraud experts, including Gartner Analyst Avivah Litan, read that statement highlighted in yellow above as an acknowledgement by Oracle that hackers may have abused credentials gained in the MICROS portal breach to plant malicious code on the point-of-sale devices run by an unknown number of MICROS customers.

“This [incident] could explain a lot about the source of some of these retail and merchant point-of-sale hacks that nobody has been able to definitively tie to any one point-of-sale services provider,” Litan told me last week. “I’d say there’s a big chance that the hackers in this case found a way to get remote access” to MICROS customers’ on-premises point-of-sale devices.”

Clearly, Visa is concerned about this possibility as well.


In my original story about the breach, I wasn’t able to reveal all the data I’d gathered about the apparent source of the attacks and attackers. A key source in that story asked that I temporarily delay publishing certain details of the investigation, specifically those known as indicators of compromise (IOCs). Basically, IOCs are list of suspect Internet addresses, domain names, filenames and other curious digital clues that are thought to connect the victim with its attacker.

I’ve been inundated all week with calls and emails from security experts asking for that very data, but sharing it wasn’t my call. That is, until yesterday (8/12/16), when Visa published a “merchant communication alert” to some customers. In that alert (PDF), Visa published IOCs that may be connected with the intrusion. These IOCs could be extremely useful to MICROS customers because the presence of Internet traffic to and from these online destinations would strongly suggest the organization’s point-of-sale systems may be similarly compromised.

Some of the addresses on this list from Visa are known to be associated with the Carbanak Gang, a group of Eastern European hackers that Russian security firm Kaspersky Lab estimates has stolen more than $1 billion from banks and retailers. Here’s the IOCs list from the alert Visa pushed out Friday:

VISA warned merchants to check their systems for any communications to and from these Internet addresses and domain names associated with a Russian organized cybercrime gang called "Carbanak."

Visa warned merchants to check their systems for any communications to and from these Internet addresses and domain names associated with a Russian organized cybercrime gang called “Carbanak.”

Thankfully, since at least one of the addresses listed above ( matched what’s on my source’s list, the source agreed to let me publish the entire thing. Here it is. I checked my source’s list and found at least five Internet addresses that were seen in both the Oracle attack and in a Sept. 2015 writeup about Carbanak by ESET Security, a Slovakian antivirus and security company. [NB: If you are unskilled at safely visiting malicious Web sites and/or handling malware, it’s probably best not to visit the addresses in the above-linked list.]

Visa also mentioned a specific POS-malware threat in its alert called “MalumPOS.” According to researchers at Trend Micro, MalumPOS is malware designed to target point-of-sale systems in hotels and related industries. In fact, Trend found that MalumPOS is set up to collect data specifically from point-of-sale systems running on Oracle’s MICROS platform.

It should come as no surprise then that many of Oracle’s biggest customers in the hospitality industry are starting to make noise, accusing Oracle of holding back key information that could help MICROS-based companies stop and clean up breaches involving malware and stolen customer credit card data.

“Oracle’s silence has been deafening,” said Michael Blake, chief executive officer at HTNG, a trade association for hotels and technology. “They are still grappling and trying to answer questions on the extent of the breach. Oracle has been invited to the last three [industry] calls this week and they are still going about trying to reach each customer individually and in the process of doing so they have done nothing but given the lame advice of changing passwords.”

The hospitality industry has been particularly hard hit by point-of-sale compromises over the past two years. Last month, KrebsOnSecurity broke the news of a breach at Kimpton Hotels (Kimpton appears to run MICROS products, but the company declined to answer questions for this story).

Kimpton joins a long list of hotel brands that have acknowledged card breaches over the last year, including Trump Hotels (twice), Hilton, Mandarin Oriental, and White Lodging (twice), Starwood Hotels and Hyatt. In many of those incidents, thieves had planted malicious software on the point-of-sale devices at restaurants and bars inside of the hotel chains. And, no doubt, many of those cash registers were run on MICROS systems.

If Oracle doesn’t exactly know which — if any — of its MICROS customers had malware on their point-of-sale systems as a result of the breach, it may be because the network intruders didn’t have any reason to interact with Oracle’s customers via the MICROS portal after stealing usernames and passwords that would allow them to remotely access customer on-premises systems. In theory, at that point the fraudsters could have bypassed Oracle altogether from then on. Continue reading →