Posts Tagged: Android

Aug 16

Road Warriors: Beware of ‘Video Jacking’

A little-known feature of many modern smartphones is their ability to duplicate video on the device’s screen so that it also shows up on a much larger display — like a TV. However, new research shows that this feature may quietly expose users to a simple and cheap new form of digital eavesdropping.

Dubbed “video jacking” by its masterminds, the attack uses custom electronics hidden inside what appears to be a USB charging station. As soon as you connect a vulnerable phone to the appropriate USB charging cord, the spy machine splits the phone’s video display and records a video of everything you tap, type or view on it as long as it’s plugged in — including PINs, passwords, account numbers, emails, texts, pictures and videos.

The part of the "video jacking" demonstration at the DEF CON security conference last week in Las Vegas.

Some of the equipment used in the “video jacking” demonstration at the DEF CON security conference last week in Las Vegas. Source: Brian Markus.

[Click here if you’re the TL;DR type and just want to know if your phone is at risk from this attack.]

Demonstrations of this simple but effective mobile spying technique were on full display at the DEF CON security conference in Las Vegas last week. I was busy chasing a story at DEF CON unrelated to the conference this year, so I missed many people and talks that I wanted to see. But I’m glad I caught up with the team behind DEF CON’s annual and infamous “Wall of Sheep,” a public shaming exercise aimed at educating people about the dangers of sending email and other plain text online communications over open wireless networks.

Brian Markus, co-founder and chief executive officer for Aries Security, said he and fellow researchers Joseph Mlodzianowski and Robert Rowley came up with the idea for video jacking when they were brainstorming about ways to expand on their “juice jacking” experiments at DEF CON in 2011.

“Juice jacking” refers to the ability to hijack stored data when the user unwittingly plugs his phone into a custom USB charging station filled with computers that are ready to suck down and record said data (both Android and iOS phones now ask users whether they trust the computer before allowing data transfers).

In contrast, video jacking lets the attacker record every key and finger stroke the user makes on the phone, so that the owner of the evil charging station can later replay the videos and see any numbers or keys pressed on the smart phone.

That’s because those numbers or keys will be raised briefly on the victim’s screen with each key press. Here’s an example: While the user may have enabled a special PIN that needs to be entered before the phone unlocks to the home screen, this method captures even that PIN as long as the device is vulnerable and plugged in before the phone is unlocked.


Most of the phones vulnerable to video jacking are Android or other HDMI-ready smartphones from Asus, Blackberry, HTC, LG, Samsung, and ZTE. This page of HDMI enabled smartphones at should not be considered all-inclusive. Here’s another list. When in doubt, search online for your phone’s make and model to find out if it is HDMI or MHL ready.

Video jacking is a problem for users of HDMI-ready phones mainly because it’s very difficult to tell a USB cord that merely charges the phone versus one that also taps the phone’s video-out capability. Also, there’s generally no warning on the phone to alert the user that the device’s video is being piped to another source, Markus said.

“All of those phones have an HDMI access feature that is turned on by default,” he said. “A few HDMI-ready phones will briefly flash something like ‘HDMI Connected’ whenever they’re plugged into a power connection that is also drawing on the HDMI feature, but most will display no warning at all. This worked on all the phones we tested with no prompting.”

Both Markus and Rowley said they did not test the attack against Apple iPhones prior to DEF CON, but today Markus said he tested it at an Apple store and the video of the iPhone 6’s home screen popped up on the display in the store without any prompt. Getting it to work on the display required a special lightning digital AV adapter from Apple, which could easily be hidden inside an evil charging station and fed an extension adapter and then a regular lightning cable in front of that.

Continue reading →

Sep 15

Tracking a Bluetooth Skimmer Gang in Mexico

-Sept. 9, 12:30 p.m. CT, Yucatan Peninsula, Mexico: Halfway down the southbound four-lane highway from Cancun to the ancient ruins in Tulum, traffic inexplicably slowed to a halt. There was some sort of checkpoint ahead by the Mexican Federal Police. I began to wonder whether it was a good idea to have brought along the ATM skimmer instead of leaving it in the hotel safe. If the cops searched my stuff, how could I explain having ultra-sophisticated Bluetooth ATM skimmer components in my backpack?

The above paragraph is an excerpt that I pulled from the body of Part II in this series of articles and video essays stemming from a recent four-day trip to Mexico. During that trip, I found at least 19 different ATMs that all apparently had been hacked from the inside and retrofitted with tiny, sophisticated devices that store and transmit stolen card data and PINs wirelessly.

In June 2015, I heard from a source at an ATM firm who wanted advice and help in reaching out to the right people about what he described as an ongoing ATM fraud campaign of unprecedented sophistication, organization and breadth. Given my focus on ATM skimming technology and innovations, I was immediately interested.

My source asked to have his name and that of his employer omitted from the story because he fears potential reprisals from the alleged organized criminal perpetrators of this scam. According to my source, several of his employer’s ATM installation and maintenance technicians in the Cancun area reported recently being approached by men with Eastern European accents, asking each tech if he would be interested in making more than 100 times his monthly salary just for providing direct, physical access to the inside of a single ATM that the technician served.

One of my source’s co-workers was later found to have accepted the bribes, which apparently had only grown larger and more aggressive after technicians in charge of specific, very busy ATMs declined an initial offer.

My source said his company fired the rogue employee who’d taken the bait, but that the employee’s actions had still been useful because experts were now able to examine the skimming technology first-hand. The company tested the hardware by installing it into ATMs that were not in service. When they turned the devices on, they discovered each component was beaconing out the same Bluetooth signal: “Free2Move.”

Turns out, Free2Move is the default name for a bluetooth beacon in a component made by a legitimate wireless communications company of the same name. I also located a sales thread in a dubious looking site that specializes in offering this technology in mini form for ATM PIN pads and card readers for $550 per component (although the site claims it won’t sell the products to scammers).

f2mThe Bluetooth circuit boards allegedly supplied by the Eastern Europeans who bribed my source’s technician were made to be discretely wired directly onto the electronic ATM circuit boards which independently serve the machine’s debit card reader and PIN pad.

Each of the bluetooth circuit boards are tiny — wafer thin and about 1 cm wide by 2 cm long. Each also comes with its own data storage device. Stolen card data can be retrieved from the bluetooth components wirelessly: The thief merely needs to be within a few meters of the compromised ATM to pull stolen card data and PINs off the devices, providing he has the secret key needed to access that bluetooth wireless connection.

Even if you knew the initial PIN code to connect to the Bluetooth wireless component on the ATM —the stolen data that is sent by the bluetooth components is encrypted. Decrypting that data requires a private key that ostensibly only the owners of this crimeware possess.

These are not your ordinary skimming devices. Most skimmers are detectable because they are designed to be affixed to the outside of the ATMs. But with direct, internal access to carefully targeted cash machines, the devices could sit for months or even years inside of compromised ATMs before being detected (depending in part on how quickly and smartly the thieves used or sold the stolen card numbers and PINs).

Not long after figuring out the scheme used by this skimmer, my source instructed his contacts in Cancun and the surrounding area to survey various ATMs in the region to see if any of these machines were emitting a Bluetooth signal called “Free2Move.” Sure enough, the area was blanketed with cash machines spitting out Free2Move signals.

Going to the cops would be useless at best, and potentially dangerous; Mexico’s police force is notoriously corrupt, and for all my source knew the skimmer scammers were paying for their own protection from the police.

Rather, he said he wanted to figure out a way to spot compromised ATMs where those systems were deployed across Mexico (but mainly in the areas popular with tourists from Europe and The United States).

When my source said he knew where I could obtain one of these skimmers in Mexico firsthand, I volunteered to scour the tourist areas in and around Cancun to look for ATMs spitting out the Free2Move bluetooth signal.

I’d worked especially hard the previous two months: So much so that July and August were record traffic months for KrebsOnSecurity, with several big breach stories bringing more than a million new readers to the site. It was time to schedule a quasi-vacation, and this was the perfect excuse. I had a huge pile of frequent flier miles burning a hole in my pocket, and I wasted no time in using those miles to book a hotel and flight to Cancun. Continue reading →

Jun 15

Critical Flaws in Apple, Samsung Devices

Normally, I don’t cover vulnerabilities about which the user can do little or nothing to prevent, but two newly detailed flaws affecting hundreds of millions of Android, iOS and Apple products probably deserve special exceptions.

keychainThe first is a zero-day bug in iOS and OS X that allows the theft of both Keychain (Apple’s password management system) and app passwords. The flaw, first revealed in an academic paper (PDF) released by researchers from Indiana University, Peking University and the Georgia Institute of Technology, involves a vulnerability in Apple’s latest operating system versions that enable an app approved for download by the Apple Store to gain unauthorized access to other apps’ sensitive data.

“More specifically, we found that the inter-app interaction services, including the keychain…can be exploited…to steal such confidential information as the passwords for iCloud, email and bank, and the secret token of Evernote,” the researchers wrote.

The team said they tested their findings by circumventing the restrictive security checks of the Apple Store, and that their attack apps were approved by the App Store in January 2015. According to the researchers, more than 88 percent of apps were “completely exposed” to the attack.

News of the research was first reported by The Register, which said that Apple was initially notified in October 2014 and that in February 2015 the company asked researchers to hold off disclosure for six months.

“The team was able to raid banking credentials from Google Chrome on the latest Mac OS X 10.10.3, using a sandboxed app to steal the system’s keychain and secret iCloud tokens, and passwords from password vaults,” The Register wrote. “Google’s Chromium security team was more responsive and removed Keychain integration for Chrome noting that it could likely not be solved at the application level. AgileBits, owner of popular software 1Password, said it could not find a way to ward off the attacks or make the malware ‘work harder’ some four months after disclosure.”

A story at suggests the malware the researchers created to run their experiments can’t directly access existing keychain entries, but instead does so indirectly by forcing users to log in manually and then capturing those credentials in a newly-created entry.

“For now, the best advice would appear to be cautious in downloading apps from unknown developers – even from the iOS and Mac App Stores – and to be alert to any occasion where you are asked to login manually when that login is usually done by Keychain,” 9to5’s Ben Lovejoy writes.


Separately, researchers at mobile security firm NowSecure disclosed they’d found a serious vulnerability in a third-party keyboard app that is pre-installed on more than 600 million Samsung mobile devices — including the recently released Galaxy S6 — that allows attackers to remotely access resources like GPS, camera and microphone, secretly install malicious apps, eavesdrop on incoming/outgoing messages or voice calls, and access pictures and text messages on vulnerable devices. Continue reading →

Aug 13

A Closer Look: Perkele Android Malware Kit

In March 2013 I wrote about Perkele, a crimeware kit designed to create malware for Android phones that can help defeat multi-factor authentication used by many banks. In this post, we’ll take a closer look at this threat, examining the malware as it is presented to the would-be victim as well as several back-end networks set up by cybercrooks who have been using mobile bots to fleece banks and their customers.

Perkele disguises itself as an various Android security applications and certiifcates.

Perkele disguises itself as various Android security applications and certificates.

Perkele is sold for $1,000, and it’s made to interact with a wide variety of malware already resident on a victim’s PC. When a victim visits his bank’s Web site, the Trojan (be it Zeus or Citadel or whatever) injects malicious code into the victim’s browser, prompting the user to enter his mobile information, including phone number and OS type.

That information is relayed back to the attacker’s control server, which injects more code into the victim’s browser prompting him to scan a QR code with his mobile device to install an additional security mechanism.

Once the victim scans the QR code, the Perkele malware is downloaded and installed, allowing the attackers to intercept incoming SMS messages sent to that phone. At that point, the malware on the victim’s PC automatically initiates a financial transaction from the victim’s account.

When the bank sends an SMS with a one-time code, Perkele intercepts that code and sends it to the attacker’s control server. Then the malicious script on the victim’s PC receives the code and completes the unauthorized transaction.

Web site security firm Versafe located a server that was being used to host malicious scripts tied to at least one Perkele operation. The company produced this report (PDF), which delves a bit deeper into the behavior and network activity generated by the crimeware kit.

Versafe’s report includes several screenshots of the Perkele application as offered to would-be victims. The malware is presented as a security certificate; it’s named “zertificate” because the victim in this case banked at a German financial institution.

Perkele disguised as a security certificate for a German bank. Source: Versafe.

Perkele disguised as a security certificate for a German bank. Source: Versafe.

A few weeks ago, I encountered the back end system for what appears to be a Perkele distribution, or perhaps some other mobile malware bot; I should note that disguising an Android banking Trojan as a security certificate is not a ruse that’s limited to Perkele: The Pincert SMS malware also employs this trick, according to F-Secure.

Anyhow, I scarcely had time to examine this particular mobile bot control panel before it was either taken down by German authorities or was moved elsewhere by the fraudsters. But it, too, was intercepting one-time codes from German banking victims using an Android malware component similarly disguised as a “zertificate.”

This Android SMS bot control panel targeted German bank customers.

This Android SMS bot control panel targeted German bank customers.

Apparently, it was fairly successful, stealing one-time codes from online banking customers of several German financial institutions, including Postbank and Comdirect.

Dozens of German banking customers were victimized by this Android bot control panel.

Dozens of German banking customers were victimized by this Android bot control panel.

In the screen grab below, we can see the main administrative page of this panel, which controls which banks should be targeted and from where the fraudulent text messages should be sent.

Continue reading →

Mar 13

Mobile Malcoders Pay to (Google) Play

An explosion in malware targeting Android users is being fueled in part by a budding market for mobile malcode creation kits, as well as a brisk market for hijacked or fraudulent developer accounts at Google Play that can be used to disguise malware as legitimate apps for sale.

An Underweb ad for Perkele

An Underweb ad for Perkele

I recently encountered an Android malware developer on a semi-private Underweb forum who was actively buying up verified developer accounts at Google Play for $100 apiece. Google charges just $25 for Android developers who wish to sell their applications through the Google Play marketplace, but it also requires the accounts to be approved and tied to a specific domain. The buyer in this case is offering $100 for sellers willing to part with an active, verified Play account that  is tied to a dedicated server.

Unsurprisingly, this particular entrepreneur also sells an Android SMS malware package that targets customers of Citibank, HSBC and ING, as well as 66 other financial institutions in Australia, France, India, Italy, Germany, New Zealand, Singapore, Spain, Switzerland and Turkey (the complete list is here). The targeted banks offer text messages as a form of multi-factor authentication, and this bot is designed to intercept all incoming SMS messages on infected Android phones.

This bot kit — dubbed “Perkele” by a malcoder who goes by the same nickname (‘perkele’ is a Finnish curse word for “devil” or “damn”) — does not appear to be terribly diabolical or sophisticated as modern mobile malware goes. Still, judging from the number and reputation of forum buyers who endorsed Perkele’s malware, it appears quite popular and to perform as advertised.

Continue reading →

Jun 12

Beware Scare Tactics for Mobile Security Apps

It may not be long before your mobile phone is beset by the same sorts of obnoxious, screen-covering, scaremongering ads pimping security software that once inundated desktop users before pop-up blockers became widely-used.

A mobile ad for SnapSecure's software

Richard M. Smith, a Boston-based security consultant, was dining out last Friday and browsing a local news site with his Android-based smart phone when his screen was taken over by an alarming message warning of page errors and viruses. Clicking anywhere on the ad took him to a Web site peddling SnapSecure, a mobile antivirus and security subscription service that bills users $5.99 a month.

“This particular ad takes over the entire screen on my Android phone, so it gives the impression of being rather ominous,” Smith said, noting that it was the second time in as many days that he’d encountered the rogue ad. He further explained that the ad just appeared when he browsed to view a new story, and that he hadn’t clicked on an ad or anything unusual.

Michael Subhan, vice president of marketing for SnapSecure, said the company traced the ads back to some rogue marketing affiliates that have since been banned from its advertising program.

“We did find out which affiliate was serving up the ad, and they will be blacklisted from the network,” Subhan said. “We have strict advertising policies, and do not tolerate rogue affiliates. Unfortunately, with the volume of advertising that we do, there are sometimes affiliates that try and get around our guidelines.”

Meanwhile, the ad linked to in the overlay image still appears to be live and redirecting users to the SnapSecure purchase page.

Jun 12

Attackers Hit Weak Spots in 2-Factor Authentication

An attack late last week that compromised the personal and business Gmail accounts of Matthew Prince, chief executive of Web content delivery system CloudFlare, revealed a subtle but dangerous security flaw in the 2-factor authentication process used in Google Apps for business customers. Google has since fixed the glitch, but the incident offers a timely reminder that two-factor authentication schemes are only as secure as their weakest component.

In a blog post on Friday, Prince wrote about a complicated attack in which miscreants were able to access a customer’s account on CloudFlare and change the customer’s DNS records. The attack succeeded, Prince said, in part because the perpetrators exploited a weakness in Google’s account recovery process to hijack his email address, which runs on Google Apps.

A Google spokesperson confirmed that the company “fixed a flaw that, under very specific conditions, existed in the account recovery process for Google Apps for Business customers.”

“If an administrator account that was configured to send password reset instructions to a registered secondary email address was successfully recovered, 2-step verification would have been disabled in the process,” the company said. “This could have led to abuse if their secondary email account was compromised through some other means. We resolved the issue last week to prevent further abuse.”

Prince acknowledged that the attackers also leveraged the fact that his recovery email address — his personal Gmail account — was not taking advantage of Google’s free 2-factor authentication offering. Prince claims that the final stage of the attack succeeded because the miscreants were able to trick his mobile phone provider — AT&T — into forwarding his voicemail to another account.

In a phone interview Monday, Prince said he received a phone call at 11:39 a.m. on Friday from a phone number in Chico, Calif. Not knowing anyone from that area, he let the call go to voicemail. Two minutes later, he received a voicemail that was a recorded message from Google saying that his personal Gmail account password had been changed. Prince said he then initiated the account recovery process himself and changed his password back, and that the hacker(s) and he continued to ping pong for control over the Gmail account, exchanging control 10 times in 15 minutes.

“The calls were being forwarded, because phone calls still came to me,” Prince said. “I didn’t realize my voicemail had been compromised until that evening when someone called me and soon after got a text message saying, ‘Hey, something is weird with your voicemail.'”

Gmail constantly nags users to tie a mobile phone number to their account, ostensibly so that those who forget their passwords or get locked out can have an automated, out-of-band way to receive a password reset code (Google also gets another way to link real-life identities connected to cell phone records with Gmail accounts that may not be so obviously tied to a specific identity). The default method of sending a reset code is via text message, but users can also select to receive the prompt via a phone call from Google.

The trouble is, Gmail users who haven’t availed themselves of Google’s 2-factor authentication offering (Google calls it “2-step verification”) are most likely at the mercy of the security of their mobile provider. For example, AT&T users who have not assigned a PIN to their voicemail accounts are vulnerable to outsiders listening to their voice messages, simply by spoofing the caller ID so that it matches the target’s own phone number. Prince said his AT&T PIN was a completely random 24-digit combination (and here I thought I was paranoid with a 12-digit PIN).

“Working with Google we believe we have discovered the vulnerability that allowed the hacker to access my personal Gmail account, which was what began the chain of events,” Prince wrote in an update to the blog post about the attack. “It appears to have involved a breach of AT&T’s systems that compromised the out-of-band verification. The upshot is that if an attacker knows your phone number and your phone number is listed as a possible recovery method for your Google account then, at best, your Google account may only be as secure as your voicemail PIN.”

AT&T officials did not respond to requests for comment.

Continue reading →

May 12

Critical Flash Update Fixes Zero-day Flaw

Adobe Systems Inc. today issued a security update to its Flash Player software. The company stressed that the update fixes a critical vulnerability that malicious actors have been using in targeted attacks.

Adobe classifies a security flaw as critical if it can be used to break into vulnerable machines without any help from users. The company said the vulnerability (CVE-2012-0779) fixed in the version released today has been exploited in targeted attacks designed to trick the user into clicking on a malicious file delivered in an email message, and that the exploit used in the attacks seen so far target Flash Player on Internet Explorer for Windows only.

Nevertheless, there are updates available for Flash Player versions designed for all operating systems that Adobe supports, including Mac, Linux and Android devices.

Continue reading →

Jun 11

Flash Player Patch Fixes Zero-Day Flaw

Adobe released an emergency security update today to fix a vulnerability that the company warned is being actively exploited in targeted attacks designed to trick the user into clicking on a malicious link delivered in an email message.

The vulnerability — a cross-site scripting bug that could be used to take actions on a user’s behalf on any Web site or Webmail provider, exists in Flash Player version and earlier for Windows, Macintosh, Linux and Solaris. Adobe recommends users update to version (on Internet Explorer, the latest, patched version is  To find out what version of Flash you have, go here.

Google appears to have already pushed out an update that fixes this flaw in Chrome. Adobe says it will ship an update to fix this flaw on Android sometime this week.

Adobe said it is still investigating whether this is exploitable in Adobe Reader and Acrobat X (10.0.2) and earlier 10.x and 9.x versions of Adobe Reader and Acrobat for Windows and Macintosh operating systems, and that it is not aware of any attacks targeting Adobe Reader or Acrobat in the wild.

Remember that if you use Internet Explorer in addition to other browsers, you will need to apply this update twice: Once to install the Flash Active X plugin for IE, and again to update other browsers, such as Firefox and Opera. Updates are available by browsing with the appropriate browser to the Flash Player Download Center. Bear in mind that updating via the Download Center involves installing Adobe’s Download Manager, which may try to foist additional software. If you’d prefer to update manually, the direct installers for Windows are available at this link. If you run into problems installing this update, you’ll want to uninstall previous versions of Flash Player and then try again.

Nov 10

Google Extends Security Bug Bounty to Gmail, YouTube, Blogger

Google on Monday said it was expanding a program to pay security researchers who discreetly report software flaws in the company’s products. The move appears aimed at engendering goodwill within the hacker community while encouraging more researchers to keep their findings private until the holes can be fixed.

Earlier this year, Google launched a program to reward researchers who directly report any security holes found in the company’s Chrome open-source browser project. With its announcement today, Google is broadening the program to include bugs reported for its Web properties, including Gmail, YouTube, Blogger and others (the company says its desktop apps — Android, Picasa and Google Desktop, etc.  are not included in the expanded bounty program).

The program is unlikely to attract those who are looking to get rich selling security vulnerabilities, as there are several less reputable places online where critical bugs in important online applications can fetch far higher prices. But the expanded bounty may just win over researchers who might otherwise post their research online, effectively alerting Google to the problem at the same time as the cyber criminal community.

“We already enjoy working with an array of researchers to improve Google security, and some individuals who have provided high caliber reports are listed on our credits page,” Google’s security team wrote on the company’s security blog. “As well as enabling us to thank regular contributors in a new way, we hope our new program will attract new researchers and the types of reports that help make our users safer.”

The standard reward for bugs will continue to be public recognition and $500, although the search giant said bugs that are particularly severe or clever could earn rewards of up to $3,133.7 (this is leet speek for “elite”).

Google said it won’t pay for bugs that involve overtly malicious attacks, such as social engineering and physical attacks or so-called “black hat search engine optimization” techniques —  and that it wouldn’t count less serious flaws such as denial-of-service bugs, or flaws in technologies recently acquired by Google.

Other companies have established bug bounty programs. For example, Mozilla, the organization behind the Firefox Web browser, for years paid researchers $500 for bugs, but recently upped the amount to $3,000.

Charlie Miller, a security researcher who has reported a large number of bugs in a variety of applications and programs, was initially critical of such a tiny bounty from one of the world’s wealthiest and most powerful businesses. But reached via e-mail Monday evening, Miller said that while he’d always like to see more money being paid to bug researchers, the relatively few companies that offer bug bounties also deserve recognition.

“With so many companies (MS, Adobe, Apple, Oracle) not paying anything, I’m very happy to see any money going out for these types of programs,” Miller wrote. “It motivates and rewards researchers.  The security of the products (or websites) that the average person uses goes up.  Also, it provides vendors with a level of control they otherwise lack.  If a researcher reports a bug and then decides they think the process is not working well, they’ll think twice about dropping it on full disclosure if they know they’ll lose their finder’s fee.”