A Sysadmin’s Holiday Checklist: Keep Your Company Safe This Festive Season – Source: heimdalsecurity.com

The holiday season is a time of celebration, but it’s also a high-risk period for cyberattacks. Cybercriminals look to exploit reduced staffing, remote work, and the surge in online activity.

As everyone scrambles for last-minute deals, these attackers find it easier than ever to slip through the cracks in your defenses.

As a system administrator at Heimdal, I know that with the right safeguards in place, you can turn a risky holiday season into a secure one.

Below, I’ll share practical, easy-to-follow steps that IT managers, sysadmins, and security professionals can apply to keep their operations secure throughout the holidays.

Prefer video? You can also check out the YouTube version:

1. Level up your endpoint security

The devices your team uses—laptops, desktops, mobile phones—are often the first targets for attackers. Over the holidays, as people travel or work from different locations, the risk increases.

Start by making sure every device has up-to-date antivirus, and endpoint protection software.

At Heimdal, we use Endpoint Detection and Response (EDR) to detect and stop threats early. (Strong endpoint security helps you identify issues before they become full-blown breaches.)

Another essential step is application whitelisting — this ensures only approved programs can run on your systems, blocking anything suspicious.

2. Get ready for a spike in phishing attempts

The holidays are prime time for phishing scams, with cybercriminals sending emails pretending to be shipping notifications, fake advent calendars, festive e-cards, or mystery boxes to trick users into clicking malicious links or sharing sensitive information.

One of our colleagues nearly fell for a Christmas mystery box scam but caught the warning signs just in time, preventing the attackers from accessing his financial information.

Watch his story here:

From Rak’s story, we understand just how vital it is to exercise caution and to train your team to recognize suspicious emails—paying attention to strange email addresses, urgent language, and unexpected attachments.

Use strong email filters to block malicious content and encourage employees to report anything that looks off. A prompt report could mean the difference between a safe holiday and a costly breach.

For more tips on helping employees identify phishing attempts, check out this resource: Phishing attacks explained: How it works, Types, Prevention and Statistics.

Phishing attacks explained: How it works, Types, Prevention and Statistics

3. Secure remote work environments

With employees working remotely, often from hotels or relatives’ houses during the holidays, your data could be at risk if their connections aren’t secure.

One easy solution is to require everyone to use a Virtual Private Network (VPN). A VPN encrypts their internet traffic, protecting sensitive data even on public Wi-Fi.

Additionally, monitor access points to your systems. If someone logs in from a new location or an unusual device, your team should be alerted immediately.

Lastly, deactivate any user accounts that won’t be used over the holidays—this reduces the chances of an old account being exploited.

If you’re looking to implement a comprehensive access control strategy, here’s a helpful Access Control Policy Template.

4. Strengthen network security

Your organization’s network is the backbone of your operations, and during the holidays, it becomes a tempting target for cybercriminals.

If you haven’t segmented your network yet, now’s the time—this means isolating sensitive areas so that even if one part of your system is breached, the damage is contained.

Implementing tools like DNS security and advanced firewalls can strengthen your defenses.

DNS security acts as a first line of defense by filtering out malicious domains and preventing data exfiltration at the DNS level.

Advanced firewalls with traffic filtering capabilities monitor and block suspicious activity in real time, while traffic visibility tools provide insight into all communications, helping you respond quickly to potential threats.

At Heimdal, we rely on Network DNS Security (Network DNS Security Tool – Heimdal® ) and Firewall Integration (Next-gen Endpoint Antivirus – NGAV + XTP with MDM) to safeguard the network.

5. Patch, patch, patch

During the holiday season, it’s a must to make sure everything is up to date. Apply the latest security patches to all software, devices, and systems.

Key steps to ensure all systems are updated

Start by conducting a full inventory of all devices and software your organization uses to ensure nothing is overlooked.

• Verify which elements have available security updates and plan a systematic approach to installing patches.
• Establish a regular update policy and automate the process where possible to minimize delays or errors.
• Test updates in a controlled environment before rolling them out widely to avoid potential service disruptions or compatibility issues.

6. Be wary of supply chain attacks

The holiday rush can strain supply chains—and attackers know it. They may target your vendors or partners to gain access to your systems.

Start by reviewing your third-party vendors. Do they meet your security standards? Are they as diligent about cybersecurity as you are?

For software supply chains:

• use tools to monitor and block unauthorized updates or dependencies
• limit the access vendors and third parties have to your systems—give them only what they absolutely need to do their job.

If you’re looking for a Third-Party Risk Management resource, check this one out: Guide to Third Party Risk Management: Dealing with Vendor Vulnerabilities.

7. Have an incident response plan in place

No matter how well-prepared you are, incidents can still happen. The difference lies in how quickly and effectively you respond.

• Make sure your incident response protocols are up to date and tailored for holiday-specific threats.
• Create an on-call rotation for your IT team so that someone is always available to address emergencies.
• Pre-authorize certain actions, like blocking suspicious accounts, so there’s no delay in responding to potential threats.

Automated Incident Response: What You Need to Know

Wrap up

The holiday season doesn’t have to be stressful when it comes to cybersecurity. By following these steps, you’ll ensure your organization is prepared to handle whatever comes its way.

At Heimdal, we believe that staying vigilant and proactive is the best gift you can give your business this holiday season. Stay safe, stay secure, and have a joyful holiday!

Additional insights – Holiday scams to watch out for

With the steps above, you’ve laid a strong foundation to protect your business. But beyond general precautions, it’s essential to stay alert to specific scams that tend to surface during this festive period.

To better understand holiday cybersecurity risks, check out the YouTube video below.

It covers how holiday distractions lead to vulnerabilities, the 30% rise in cyberattacks during December, and tactics like spear phishing and malware disguised as deals. It also highlights the Target breach and shares practical tips like using multi-factor authentication and staying cautious with emails.

These threats often go beyond standard phishing and use seasonal themes, workplace roles, and trust to catch people off guard.

Now, let’s take a closer look at common holiday scams to watch out for.

Spear phishing

Attackers craft highly targeted emails that appear to come from executives, vendors, or trusted partners. They often reference holiday bonuses, event invitations, or urgent requests tied to the festive period.

Once clicked, malicious links or attachments can harvest credentials or deploy malware.

For example, an email might seem to originate from the CFO asking for urgent approval of a holiday expense but is actually a cleverly disguised phishing attempt.

Malicious holiday E-cards

Friendly digital holiday greetings can be weaponized by cybercriminals. Attackers embed malicious links or attachments disguised as festive animations.

Clicking the link silently installs malware, such as spyware or ransomware, that can spread through corporate networks.

A simple holiday e-card could secretly deploy a keylogger, capturing login credentials to sensitive systems.

Insider threat

The holidays can heighten stress and distraction, potentially fueling insider threats.

Dissatisfied employees might steal data or grant unauthorized access to attackers. Financially motivated insiders may sell confidential information, while negligent behavior can lead to accidental exposure.

An employee with elevated privileges could exfiltrate financial records, later selling them on the dark web.

Unsecured online shopping

Fake e-commerce sites offering huge discounts proliferate during the holidays.

If employees use these sites to make corporate purchases, they may unknowingly hand over payment details or download malware.

Businesses that do corporate gifting should verify the legitimacy of online retailers to prevent data theft.

Corporate travel scams

Fake travel booking platforms offer significant discounts on flights or hotels but are designed to steal payment data.

An employee arranging a year-end corporate retreat could fall victim, unknowingly providing sensitive information to a fraudulent site that compromises corporate credit cards or accounts.

Just like the Booking.com scam reported earlier this year.

Business email compromise (BEC) scams

BEC attacks spike during the end-of-year financial rush. Attackers impersonate executives and send requests for urgent wire transfers or sensitive financial data.

With insider knowledge and believable corporate language, these scams can slip past defenses.

An email appearing to be from the CEO might demand immediate payment to a holiday vendor, resulting in substantial financial loss if not verified.

Wrapping up the wrap-up

If you’ve read this far, you got this. Stay safe. Even if cybercriminals try to play the Grinch, with the right defenses, they won’t steal Christmas :).

By staying alert to these seasonal schemes and applying these holiday cybersecurity tips, you’re well on your way to keeping your organization secure.

About the author

Alex Panait, System Administrator @ Heimdal

This article was brought to you by Alex Panait, System Administrator at Heimdal, with editing support from Antonia Din and Madalina Popovici.

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