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8
Feb 20

Dangerous Domain Corp.com Goes Up for Sale

As an early domain name investor, Mike O’Connor had by 1994 snatched up several choice online destinations, including bar.com, cafes.com, grill.com, place.com, pub.com and television.com. Some he sold over the years, but for the past 26 years O’Connor refused to auction perhaps the most sensitive domain in his stable — corp.com. It is sensitive because years of testing shows whoever wields it would have access to an unending stream of passwords, email and other proprietary data belonging to hundreds of thousands of systems at major companies around the globe.

Now, facing 70 and seeking to simplify his estate, O’Connor is finally selling corp.com. The asking price — $1.7 million — is hardly outlandish for a 4-letter domain with such strong commercial appeal. O’Connor said he hopes Microsoft Corp. will buy it, but fears they won’t and instead it will get snatched up by someone working with organized cybercriminals or state-funded hacking groups bent on undermining the interests of Western corporations.

One reason O’Connor hopes Microsoft will buy it is that by virtue of the unique way Windows handles resolving domain names on a local network, virtually all of the computers trying to share sensitive data with corp.com are somewhat confused Windows PCs. More importantly, early versions of Windows actually encouraged the adoption of insecure settings that made it more likely Windows computers might try to share sensitive data with corp.com.

At issue is a problem known as “namespace collision,” a situation where domain names intended to be used exclusively on an internal company network end up overlapping with domains that can resolve normally on the open Internet.

Windows computers on an internal corporate network validate other things on that network using a Microsoft innovation called Active Directory, which is the umbrella term for a broad range of identity-related services in Windows environments. A core part of the way these things find each other involves a Windows feature called “DNS name devolution,” which is a kind of network shorthand that makes it easier to find other computers or servers without having to specify a full, legitimate domain name for those resources.

For instance, if a company runs an internal network with the name internalnetwork.example.com, and an employee on that network wishes to access a shared drive called “drive1,” there’s no need to type “drive1.internalnetwork.example.com” into Windows Explorer; typing “\\drive1\” alone will suffice, and Windows takes care of the rest.

But things can get far trickier with an internal Windows domain that does not map back to a second-level domain the organization actually owns and controls. And unfortunately, in early versions of Windows that supported Active Directory — Windows 2000 Server, for example — the default or example Active Directory path was given as “corp,” and many companies apparently adopted this setting without modifying it to include a domain they controlled.

Compounding things further, some companies then went on to build (and/or assimilate) vast networks of networks on top of this erroneous setting.

Now, none of this was much of a security concern back in the day when it was impractical for employees to lug their bulky desktop computers and monitors outside of the corporate network. But what happens when an employee working at a company with an Active Directory network path called “corp” takes a company laptop to the local Starbucks?

Chances are good that at least some resources on the employee’s laptop will still try to access that internal “corp” domain. And because of the way DNS name devolution works on Windows, that company laptop online via the Starbucks wireless connection is likely to then seek those same resources at “corp.com.”

In practical terms, this means that whoever controls corp.com can passively intercept private communications from hundreds of thousands of computers that end up being taken outside of a corporate environment which uses this “corp” designation for its Active Directory domain.

INSTANT CORPORATE BOTNET, ANYONE?

That’s according to Jeff Schmidt, a security expert who conducted a lengthy study on DNS namespace collisions funded in part by grants from the U.S. Department of Homeland Security. As part of that analysis, Schmidt convinced O’Connor to hold off selling corp.com so he and others could better understand and document the volume and types of traffic flowing to it each day.

During an eight month analysis of wayward internal corporate traffic destined for corp.com in 2019, Schmidt found more than 375,000 Windows PCs were trying to send this domain information it had no business receiving — including attempts to log in to internal corporate networks and access specific file shares on those networks.

For a brief period during that testing, Schmidt’s company JAS Global Advisors accepted connections at corp.com that mimicked the way local Windows networks handle logins and file-sharing attempts.

“It was terrifying,” Schmidt said. “We discontinued the experiment after 15 minutes and destroyed the data. A well-known offensive tester that consulted with JAS on this remarked that during the experiment it was ‘raining credentials’ and that he’d never seen anything like it.”

Likewise, JAS temporarily configured corp.com to accept incoming email.

“After about an hour we received in excess of 12 million emails and discontinued the experiment,” Schmidt said. “While the vast majority of the emails were of an automated nature, we found some of the emails to be sensitive and thus destroyed the entire corpus without further analysis.”

Schmidt said he and others concluded that whoever ends up controlling corp.com could have an instant botnet of well-connected enterprise machines.

“Hundreds of thousands of machines directly exploitable and countless more exploitable via lateral movement once in the enterprise,” he said. “Want an instant foothold into about 30 of the world’s largest companies according to the Forbes Global 2000? Control corp.com.” Continue reading →


29
Jan 20

Sprint Exposed Customer Support Site to Web

Fresh on the heels of a disclosure that Microsoft Corp. leaked internal customer support data to the Internet, mobile provider Sprint has addressed a mix-up in which posts to a private customer support community were exposed to the Web.

KrebsOnSecurity recently contacted Sprint to let the company know that an internal customer support forum called “Social Care” was being indexed by search engines, and that several months worth of postings about customer complaints and other issues were viewable without authentication to anyone with a Web browser.

A redacted screen shot of one Sprint customer support thread exposed to the Web.

A Sprint spokesperson responded that the forum was indeed intended to be a private section of its support community, but that an error caused the section to become public.

“These conversations include minimal customer information and are used for frontline reps to escalate issues to managers,” said Lisa Belot, Sprint’s communications manager.

A review of the exposed support forum by this author suggests that while none of the posts exposed customer information such as payment card data, a number of them did include customer account information, such customer names, device identifiers and in some cases location information.

Perhaps more importantly for Sprint and its customers, the forum also included numerous links and references to internal tools and procedures. This sort of information would no doubt be of interest to scammers seeking to conduct social engineering attacks against Sprint employees as way to perpetrate other types of fraud, including unauthorized SIM swaps or in gleaning more account information from targeted customers. Continue reading →


24
Jan 20

Does Your Domain Have a Registry Lock?

If you’re running a business online, few things can be as disruptive or destructive to your brand as someone stealing your company’s domain name and doing whatever they wish with it. Even so, most major Web site owners aren’t taking full advantage of the security tools available to protect their domains from being hijacked. Here’s the story of one recent victim who was doing almost everything possible to avoid such a situation and still had a key domain stolen by scammers.

On December 23, 2019, unknown attackers began contacting customer support people at OpenProvider, a popular domain name registrar based in The Netherlands. The scammers told the customer representatives they had just purchased from the original owner the domain e-hawk.net — which is part of a service that helps Web sites detect and block fraud — and that they were having trouble transferring the domain from OpenProvider to a different registrar.

The real owner of e-hawk.net is Raymond Dijkxhoorn, a security expert and entrepreneur who has spent much of his career making life harder for cybercrooks and spammers. Dijkxhoorn and E-HAWK’s CEO Peter Cholnoky had already protected their domain with a “registrar lock,” a service that requires the registrar to confirm any requested changes with the domain owner via whatever communications method is specified by the registrant.

In the case of e-hawk.net, however, the scammers managed to trick an OpenProvider customer service rep into transferring the domain to another registrar with a fairly lame social engineering ruse — and without triggering any verification to the real owners of the domain.

Specifically, the thieves contacted OpenProvider via WhatsApp, said they were now the rightful owners of the domain, and shared a short screen grab video showing the registrar’s automated system blocking the domain transfer (see video below).

“The support agent helpfully tried to verify if what the [scammers] were saying was true, and said, ‘Let’s see if we can move e-hawk.net from here to check if that works’,” Dijkxhoorn said. “But a registrar should not act on instructions coming from a random email address or other account that is not even connected to the domain in question.”

Dijkxhoorn shared records obtained from OpenProvider showing that on Dec. 23, 2019, the e-hawk.net domain was transferred to a reseller account within OpenProvider. Just three days later, that reseller account moved e-hawk.net to another registrar — Public Domain Registry (PDR).

“Due to the previously silent move to another reseller account within OpenProvider, we were not notified by the registrar about any changes,” Dijkxhoorn said. “This fraudulent move was possible due to successful social engineering towards the OpenProvider support team. We have now learned that after the move to the other OpenProvider account, the fraudsters could silently remove the registrar lock and move the domain to PDR.”

REGISTRY LOCK

Dijkxhoorn said one security precaution his company had not taken with their domain prior to the fraudulent transfer was a “registry lock,” a more stringent, manual (and sometimes offline) process that effectively neutralizes any attempts by fraudsters to social engineer your domain registrar.

With a registry lock in place, your registrar cannot move your domain to another registrar on its own. Doing so requires manual contact verification by the appropriate domain registry, such as Verisign — which is the authoritative registry for all domains ending in .com, .net, .name, .cc, .tv, .edu, .gov and .jobs. Other registries handle locks for specific top-level or country-code domains, including Nominet (for .co.uk or .uk domains), EURID (for .eu domains), CNNIC for (for .cn) domains, and so on.

According to data provided by digital brand protection firm CSC, while domains created in the top three most registered top-level domains (.com, .jp and .cn) are eligible for registry locks, just 22 percent of domain names tracked in Forbes’ list of the World’s Largest Public Companies have secured registry locks.

Unfortunately, not all registrars support registry locks (a list of top-level domains that do allow registry locks is here, courtesy of CSC). But as we’ll see in a moment, there are other security precautions that can and do help if your domain somehow ends up getting hijacked.

Dijkxhoorn said his company first learned of the domain theft on Jan. 13, 2020, which was the date the fraudsters got around to changing the domain name system (DNS) settings for e-hawk.net. That alert was triggered by systems E-HAWK had previously built in-house that continually monitor their stable of domains for any DNS changes.

By the way, this continuous monitoring of one’s DNS settings is a powerful approach to help blunt attacks on your domains and DNS infrastructure. Anyone curious about why this might be a good approach should have a look at this deep-dive from 2019 on “DNSpionage,” the name given to the exploits of an Iranian group that has successfully stolen countless passwords and VPN credentials from major companies via DNS-based attacks. Continue reading →


13
Jan 20

Phishing for Apples, Bobbing for Links

Anyone searching for a primer on how to spot clever phishing links need look no further than those targeting customers of Apple, whose brand by many measures remains among the most-targeted. Past stories here have examined how scammers working with organized gangs try to phish iCloud credentials from Apple customers who have a mobile device that is lost or stolen. Today’s piece looks at the well-crafted links used in some of these lures.

KrebsOnSecurity heard from a reader in South Africa who recently received a text message stating his lost iPhone X had been found. The message addressed him by name and said he could view the location of his wayward device by visiting the link https://maps-icloud[.]com — which is most definitely not a legitimate Apple or iCloud link and is one of countless spoofing Apple’s “Find My” service for locating lost Apple devices.

While maps-icloud[.]com is not a particularly convincing phishing domain, a review of the Russian server where that domain is hosted reveals a slew of far more persuasive links spoofing Apple’s brand. Almost all of these include encryption certificates (start with “https://) and begin with the subdomains “apple.” or “icloud.” followed by a domain name starting with “com-“.

Here are just a few examples (the phishing links in this post have been hobbled with brackets to keep them from being clickable):

apple.com-support[.]id
apple.com-findlocation[.]id
apple.com-sign[.]in
apple.com-isupport[.]in
icloud.com-site-log[.]in

Savvy readers here no doubt already know this, but to find the true domain referenced in a link, look to the right of “http(s)://” until you encounter the first forward slash (/). The domain directly to the left of that first slash is the true destination; anything that precedes the second dot to the left of that first slash is a subdomain and should be ignored for the purposes of determining the true domain name.

For instance, in the case of the imaginary link below, example.com is the true destination, not apple.com:

https://www.apple.com.example.com/findmyphone/

Of course, any domain can be used as a redirect to any other domain. Case in point: Targets of the phishing domains above who are undecided on whether the link refers to a legitimate Apple site might seek to load the base domain into a Web browser (minus the customization in the remainder of the link after the first forward slash). To assuage such concerns, the phishers in this case will forward anyone visiting those base domains to Apple’s legitimate iCloud login page (icloud.com).

The best advice to sidestep phishing scams is to avoid clicking on links that arrive unbidden in emails, text messages and other mediums. Most phishing scams invoke a temporal element that warns of dire consequences should you fail to respond or act quickly. If you’re unsure whether the message is legitimate, take a deep breath and visit the site or service in question manually — ideally, using a browser bookmark so as to avoid potential typosquatting sites.


9
Oct 19

Patch Tuesday Lowdown, October 2019 Edition

On Tuesday Microsoft issued software updates to fix almost five dozen security problems in Windows and software designed to run on top of it. By most accounts, it’s a relatively light patch batch this month. Here’s a look at the highlights.

Happily, only about 15 percent of the bugs patched this week earned Microsoft’s most dire “critical” rating. Microsoft labels flaws critical when they could be exploited by miscreants or malware to seize control over a vulnerable system without any help from the user.

Also, Adobe has kindly granted us another month’s respite from patching security holes in its Flash Player browser plugin.

Included in this month’s roundup is something Microsoft actually first started shipping in the third week of September, when it released an emergency update to fix a critical Internet Explorer zero-day flaw (CVE-2019-1367) that was being exploited in the wild. Continue reading →


18
Sep 19

Before He Spammed You, this Sly Prince Stalked Your Mailbox

A reader forwarded what he briefly imagined might be a bold, if potentially costly, innovation on the old Nigerian prince scam that asks for help squirreling away millions in unclaimed fortune: It was sent via the U.S. Postal Service, with a postmarked stamp and everything.

In truth these old fashioned “advance fee” or “419” scams predate email and have circulated via postal mail in various forms and countries over the years.

The recent one pictured below asks for help in laundering some $11.6 million from an important dead person that anyway has access to a secret stash of cash. Any suckers who bite are strung along for weeks while imaginary extortionists or crooked employees at these bureaucratic institutions demand licenses, bribes or other payments before disbursing any funds. Those funds never arrive, no matter how much money the sucker gives up.

This type of “advance fee” or “419” scam letter is common in spam, probably less so via USPS.

It’s easy to laugh at this letter, because it’s sometimes funny when scammers try so hard. But then again, maybe the joke’s on us because sending these scams via USPS makes them even more appealing to the people most vulnerable: Older individuals with access to cash but maybe not all their marbles.  Continue reading →


30
Aug 19

Phishers are Angling for Your Cloud Providers

Many companies are now outsourcing their marketing efforts to cloud-based Customer Relationship Management (CRM) providers. But when accounts at those CRM providers get hacked or phished, the results can be damaging for both the client’s brand and their customers. Here’s a look at a recent CRM-based phishing campaign that targeted customers of Fortune 500 construction equipment vendor United Rentals.

Stamford, Ct.-based United Rentals [NYSE:URI] is the world’s largest equipment rental company, with some 18,000 employees and earnings of approximately $4 billion in 2018. On August 21, multiple United Rental customers reported receiving invoice emails with booby-trapped links that led to a malware download for anyone who clicked.

While phony invoices are a common malware lure, this particular campaign sent users to a page on United Rentals’ own Web site (unitedrentals.com).

A screen shot of the malicious email that spoofed United Rentals.

In a notice to customers, the company said the unauthorized messages were not sent by United Rentals. One source who had at least two employees fall for the scheme forwarded KrebsOnSecurity a response from UR’s privacy division, which blamed the incident on a third-party advertising partner.

“Based on current knowledge, we believe that an unauthorized party gained access to a vendor platform United Rentals uses in connection with designing and executing email campaigns,” the response read.

“The unauthorized party was able to send a phishing email that appears to be from United Rentals through this platform,” the reply continued. “The phishing email contained links to a purported invoice that, if clicked on, could deliver malware to the recipient’s system. While our investigation is continuing, we currently have no reason to believe that there was unauthorized access to the United Rentals systems used by customers, or to any internal United Rentals systems.”

United Rentals told KrebsOnSecurity that its investigation so far reveals no compromise of its internal systems.

“At this point, we believe this to be an email phishing incident in which an unauthorized third party used a third-party system to generate an email campaign to deliver what we believe to be a banking trojan,” said Dan Higgins, UR’s chief information officer.

United Rentals would not name the third party marketing firm thought to be involved, but passive DNS lookups on the UR subdomain referenced in the phishing email (used by UL for marketing since 2014 and visible in the screenshot above as “wVw.unitedrentals.com”) points to Pardot, an email marketing division of cloud CRM giant Salesforce. Continue reading →


13
Aug 19

Patch Tuesday, August 2019 Edition

Most Microsoft Windows (ab)users probably welcome the monthly ritual of applying security updates about as much as they look forward to going to the dentist: It always seems like you were there just yesterday, and you never quite know how it’s all going to turn out. Fortunately, this month’s patch batch from Redmond is mercifully light, at least compared to last month.

Okay, maybe a trip to the dentist’s office is still preferable. In any case, today is the second Tuesday of the month, which means it’s once again Patch Tuesday (or — depending on your setup and when you’re reading this post — Reboot Wednesday). Microsoft today released patches to fix some 93 vulnerabilities in Windows and related software, 35 of which affect various Server versions of Windows, and another 70 that apply to the Windows 10 operating system.

Although there don’t appear to be any zero-day vulnerabilities fixed this month — i.e. those that get exploited by cybercriminals before an official patch is available — there are several issues that merit attention.

Chief among those are patches to address four moderately terrifying flaws in Microsoft’s Remote Desktop Service, a feature which allows users to remotely access and administer a Windows computer as if they were actually seated in front of the remote computer. Security vendor Qualys says two of these weaknesses can be exploited remotely without any authentication or user interaction.

“According to Microsoft, at least two of these vulnerabilities (CVE-2019-1181 and CVE-2019-1182) can be considered ‘wormable’ and [can be equated] to BlueKeep,” referring to a dangerous bug patched earlier this year that Microsoft warned could be used to spread another WannaCry-like ransomware outbreak. “It is highly likely that at least one of these vulnerabilities will be quickly weaponized, and patching should be prioritized for all Windows systems.”

Fortunately, Remote Desktop is disabled by default in Windows 10, and as such these flaws are more likely to be a threat for enterprises that have enabled the application for various purposes. For those keeping score, this is the fourth time in 2019 Microsoft has had to fix critical security issues with its Remote Desktop service.

For all you Microsoft Edge and Internet Exploiter Explorer users, Microsoft has issued the usual panoply of updates for flaws that could be exploited to install malware after a user merely visits a hacked or booby-trapped Web site. Other equally serious flaws patched in Windows this month could be used to compromise the operating system just by convincing the user to open a malicious file (regardless of which browser the user is running). Continue reading →


5
Aug 19

The Risk of Weak Online Banking Passwords

If you bank online and choose weak or re-used passwords, there’s a decent chance your account could be pilfered by cyberthieves — even if your bank offers multi-factor authentication as part of its login process. This story is about how crooks increasingly are abusing third-party financial aggregation services like Mint, PlaidYodlee, YNAB and others to surveil and drain consumer accounts online.

Crooks are constantly probing bank Web sites for customer accounts protected by weak or recycled passwords. Most often, the attacker will use lists of email addresses and passwords stolen en masse from hacked sites and then try those same credentials to see if they permit online access to accounts at a range of banks.

A screenshot of a password-checking tool being used to target Chase Bank customers who re-use passwords from other sites. Image: Hold Security.

From there, thieves can take the list of successful logins and feed them into apps that rely on application programming interfaces (API)s from one of several personal financial data aggregators which help users track their balances, budgets and spending across multiple banks.

A number of banks that do offer customers multi-factor authentication — such as a one-time code sent via text message or an app — have chosen to allow these aggregators the ability to view balances and recent transactions without requiring that the aggregator service supply that second factor. That’s according to Brian Costello, vice president of data strategy at Yodlee, one of the largest financial aggregator platforms.

Costello said while some banks have implemented processes which pass through multi-factor authentication (MFA) prompts when consumers wish to link aggregation services, many have not.

“Because we have become something of a known quantity with the banks, we’ve set up turning off MFA with many of them,” Costello said.  “Many of them are substituting coming from a Yodlee IP or agent as a factor because banks have historically been relying on our security posture to help them out.”

Such reconnaissance helps lay the groundwork for further attacks: If the thieves are able to access a bank account via an aggregator service or API, they can view the customer’s balance(s) and decide which customers are worthy of further targeting.

This targeting can occur in at least one of two ways. The first involves spear phishing attacks to gain access to that second authentication factor, which can be made much more convincing once the attackers have access to specific details about the customer’s account — such as recent transactions or account numbers (even partial account numbers).

The second is through an unauthorized SIM swap, a form of fraud in which scammers bribe or trick employees at mobile phone stores into seizing control of the target’s phone number and diverting all texts and phone calls to the attacker’s mobile device.

But beyond targeting customers for outright account takeovers, the data available via financial aggregators enables a far more insidious type of fraud: The ability to link the target’s bank account(s) to other accounts that the attackers control.

That’s because PayPal, Zelle, and a number of other pure-play online financial institutions allow customers to link accounts by verifying the value of microdeposits. For example, if you wish to be able to transfer funds between PayPal and a bank account, the company will first send a couple of tiny deposits  — a few cents, usually — to the account you wish to link. Only after verifying those exact amounts will the account-linking request be granted. Continue reading →