Every year, on the first Monday after Thanksgiving, two things happen. First, online retailers slash prices and the internet goes on its annual shopping spree. And second, criminals swarm on unwitting businesses, launching large-scale hacks and clever scams.

Digital sales reach up to $3.19 billion on Cyber Monday. Amazon alone generated 36 percent of all online sales last Cyber Monday, accounting for an estimated $1 billion. With so much money changing hands over the internet, the ramifications of a cyber-attack would be huge.

What happens if a DDoS attack hits Amazon’s service provider? The website goes down. Digital sales grind to a halt. And millions in revenue go down the drain as they watch their most lucrative day of the year pass them by.

On Cyber Monday 2014, a DNS provider was hit with a fairly rudimentary DDoS attack. While it lacked the large-scale impact of today’s Mirai botnets, their clients lost vital business. In another holiday attack, criminals hacked Target and stole sensitive data from 70 million customers.

Disruption and data-theft have become tried-and-true tactics for criminals on Cyber Monday. And with Mirai botnets capable of launching massive DDoS attacks, these could become even more devastating, reminiscent of the Dyn attack but with more far-reaching monetary consequences.

However, in their current form, DDoS attacks are still relatively simple. They work by exploiting a fundamental flaw in the Internet. But what if this Cyber Monday, a highly targeted and sophisticated DDoS attack took an organization hostage? By overwhelming a company — or a series of companies — with junk traffic, an attacker could demand a large sum to stop the attack. Whether to manipulate the market or for financial gain, all signs point toward increasingly advanced DDoS attacks.

The implications for this Cyber Monday are clear — businesses need to be prepared. From DDoS to ransomware, every organization can expect to be hit. Companies should bolster their cyber defense well before the holidays, because in security, as in life, you should expect the best, but prepare for the worst.

To learn more about the types of attack you could face, check out my thoughts on DDoS and the IoT.