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Black Friday Cyberattacks: Businesses Face Surge of Malware, Ransomware on U.S. Shopping Holiday

Cyber Monday and Black Friday are the proverbial holiday shopping seasons for cybercriminals and their strategic cyberattacks, including malware, ransomware and phishing attacks. Eager online shoppers are hurried to fill holiday dreams — often at the detriment of cybersecurity best practices and common sense.

According to Adobe Analytics, consumers spent $7.4 billion online during this year’s Black Friday event, up $1.2 billion over 2018. Those numbers jumped for Cyber Monday, where retailers collected $9.4 billion in online sales on the frantic shopping holiday.

That kind of volume — in terms of both people and dollars — makes for a lucrative target for the modern cybercriminal. In 2018, SonicWall Capture Labs threat researchers discovered a spike in ransomware attacks during the Black Friday and Cyber Monday shopping events, as well as a 45% jump in phishing attacks.

Black Friday and Cyber Monday in 2019 resulted in much of the same. SonicWall Capture Labs threat researchers recorded* a double-digit malware spike (63%) in the U.S. between the eight-day holiday shopping window from Nov. 25 to Dec. 2.

  • 129.3 million malware attacks (63% increase over 2018)
  • 639,355 ransomware attacks (14% decrease over 2018)
  • 51% increase in phishing attacks on Black Friday (compared to the average day in 2019)

Cyber Monday attacks dips, Black Friday takes the hit

Cybercriminals weren’t waiting until Cyber Monday to launch their campaigns, either. In the U.S., both malware (130%) and ransomware attacks (69%) were up on Black Friday compared to 2018. This trend continued on Cyber Sunday with increases in malware (107%) and ransomware (9%).

Interestingly, ransomware attacks were down on Cyber Monday (-41%) and Small Business Saturday (-55%), resulting in an overall 14% decrease in U.S. ransomware attacks during the eight-day shopping window.

Malicious Android apps spotted during Black Friday

It’s no secret that much of holiday shopping is done on mobile apps. Busy online shoppers often leverage mobile apps that keep track of deals, provide discount coupons and offer the convenience of skipping long lines at shopping malls.

To diversify their attack strategies, cybercriminals and malware writers use this opportunity to spread malware under the guise of shopping and deal-related apps — particularly during this eight-day Thanksgiving holiday shopping window.

In the past few weeks alone, SonicWall Capture Labs threat researchers observed a number of malicious Android apps that use the shopping theme to trick users into downloading and installing these apps.

One of the more notable malicious apps is this Amazon Shopping Hack, which is tied to a range of survey scams that attempt to steal user data and sensitive information.

Name: Amazon Shopping Hack
Package: com.amazon.mShop.android.shopping.hack
SHA: fa87b95eead4d43b2ca4b6d8c945db082b4886b395b3c3731dee9b7c19344bfa

After execution, this app shows a human verification page to continue using this app. This “verification” essentially leads to survey-related scams that attempt to extract sensitive user information, such as email address, credit card details, address, etc.

One of the domains contacted by this app during execution is mobverify.com. A quick search about this domain revealed a number of other survey related pages:

The mobverify.com domain is associated with a number of malevolent apps, survey scam links and malicious executables. During analysis, we observed a GET request to mobverify.com, which downloads a json file containing a list of different survey scams:

For additional examples of malicious Android apps, please review the in-depth findings of the Capture Labs threat team: Malicious Android Apps Observed During Thanksgiving Season 2019.

Intelligence for this report was sourced from real-world data gathered by the SonicWall Capture Threat Network, which securely monitors and collects information from global devices and resources including more than 1 million security sensors in nearly 215 countries and territories.


* As a best practice, SonicWall routinely optimizes its methodologies for data collection, analysis and reporting. This includes improvements to data cleansing, changes in data sources and consolidation of threat feeds. Figures published in previous reports may have been adjusted across different time periods, regions or industries.

Critical Business Threats: Ransomware and Employee Online Shopping

According to a recent PWC survey, 54 percent of respondents buy products online every month. And millions of employees shopped online yesterday with their work devices on business networks. The critical business threat: Will any of your business computers or networks get infected with malware when employees make personal online purchases?

We believe so, and our SonicWall Global Response Intelligent Defense (GRID) network research backs this up.

Good News: Chip Cards Are Working

Research gathered through the SonicWall GRID Network indicates that the new chip-and-sign credit cards and point of sale (POS) systems are more effective than legacy technologies in detecting and blocking breaches. After big data breaches at retailers like Target and Home Depot, many retailers upgraded to chip-based POS systems.

Whenever new malware is discovered, we create a software signature set that is automatically propagated to all of our customers’ firewalls, to help keep their systems safe from attack. In 2014, before the new chip cards and POS systems, our team released 14 new POS-related malware signature sets.

In 2015, this number decreased to nine new POS malware signature sets. And in 2016 to-date, after the broad adoption of chip-based cards and readers, we have only had to release a single new signature.

Bad News: SPAM Is Now a Huge Business Threat

As POS systems have become harder to hack, the bad guys are looking for more efficient ways to steal online. Falling back on the tried and true email-based phishing attacks, personal shopping phishing emails are now a real threat to your business systems and networks.

Our email security research team observes that SPAM email usually increases in volume significantly during Cyber Week, starting the week before Black Friday, then drops off after Cyber Monday. Our numbers show a dramatic 2x increase in SPAM this year from 2015. In the run-up to Thanksgiving and Black Friday we saw 110 percent growth, increasing to 143 percent growth through Cyber Monday.

One of our SPAM honeypots collected the following data for Cyber Week:

  • Average number of SPAM messages 2015: 33,725 a day
  • Average number of SPAM messages 2016: 82,888 a day

More Bad News: Ransomware Targets Businesses

Increasingly we are finding that if malware makes it into your business network, it will be ransomware. First released in 1989, ransomware can infect your system and lock out users from accessing devices or files. When the victim pays a ransom (usually electronic money or bitcoins) the device can be unlocked by the hackers. Needless to say, ransomware can put your business-critical data and systems at risk.

Network Security Must-Haves

Online shopping will only continue to grow, especially over holidays, so it’s important to be proactive to keep your business systems protected. Along with monitoring employee access and updating policies, here are some must-haves.

  • Ensure your firewall is next-generation with content filtering on, including encryption scanning and packet filters; your goal is to monitor and inspect all incoming data and stop ransomware
  • Consider a cloud-based protection service like our Capture Advanced Threat Protection Service; a good one will speed up your response time, leverage the power of multiple engines to stop zero-day attacks, and automate remediation
  • Manage network bandwidth to limit or stop streaming; streaming is one of the easiest ways to let malware in
  • We strongly recommend EV SSL certificates for every external business website
  • Vet your SSL certificates and sources, to ensure they are publicly rooted and aren’t bringing in malware from the dark web
  • Audit your SSL certificates regularly to ensure they are up to date
  • It goes without saying but back up your data regularly; if ransomware does infect your network you will need to quickly access business-critical data

Online Shopping Safety for Consumers

  • If you don’t have one yet, upgrade to a chip-based credit card
  • Always look for an EV SSL certified logo on sites you shop
  • Use mobile devices (tablets or phones) and shop with store apps from businesses you know and trust; these apps are vetted and tested
  • Avoid shopping on sites with a Windows-based laptop; Windows is the most targeted operating system (OS) for hackers
  • Remain on the site until you complete a transaction; don’t follow redirects
  • Stay current with the latest OS software updates on your devices so you have the latest security patches; always update from the trusted site of the software provider, not a third-party site or a pop up
  • Update your apps regularly, especially ones that you provide sensitive data to: credit card numbers, banking and health information
  • Create complex, hard-to-crack passwords and keep them in a secure place
  • Change your passwords often and keep them hidden ­– not on sticky notes on your computer