What is Zero-Day?

Chances are you’ve heard of zero-day. But are you familiar with what it means? Zero-day describes recently discovered security vulnerabilities that hackers can use to access your systems. The term itself refers to the developer or vendor having had zero days to fix the vulnerability. So, a zero-day attack occurs when a hacker exploits that vulnerability before being addressed.

Zero-day typically incorporates the words vulnerability, exploit, or attack. Here’s what each of those derivatives means:

• Zero-Day Vulnerability: This term reflects a software vulnerability discovered by attackers before a vendor. Because no patch exists for the vulnerability, a hacker’s attack will likely succeed.
• Zero-Day Exploit: An exploit is the tactic or technique to attack a system with an unknown vulnerability.
• Zero-Day Attack: When a hacker uses an exploit to damage or steal data from a system affected by a vulnerability, it’s called a zero-day attack. So, a zero-day attack happens when a hacker releases malware to exploit the unknown vulnerability.

Think of it as a sequence. First, the vulnerability presents an avenue for hackers. Second, the attacker uses a tool to perform an exploit to capitalize on the exposure. Third, the final step in the process is launching the zero-day attack.

By the way, once a zero-day vulnerability has gone public, it becomes an n-day or one-day vulnerability.

Zero-day vulnerabilities typically get added to the Common Vulnerabilities and Exposures (CVE) lists. As a result, the CVE list acts like a dictionary for publicly disclosed cybersecurity vulnerabilities. Records include an identification number, description, and at least one public reference.

Executing a Zero-Day Attack

As you might expect, the attack itself takes advantage of the vulnerability. Those vulnerabilities are associated with improper computer configurations, improper security configurations, or even programming errors on behalf of developers.

Hackers write exploit codes to identify the vulnerabilities. In addition, they might even purchase the code via the dark web. Once identified, the vulnerabilities leave the door wide open for cybercriminals to inject malware, otherwise known as zero-day malware or as a zero-day exploit.

The malware often gets delivered through social engineering or phishing tactics. After the exploit gets downloaded on devices, the zero-day attack gets executed. As a result, the attack allows hackers to:

• Steal data
• Enable remote control of devices
• Install additional malware
• Corrupt files
• Install Spyware to steal sensitive data.

Exploits can take months or years to happen. Developers can often patch vulnerabilities, though, before too much damage occurs.

Recent Examples of Zero-Day

During the last couple of years, there have been several zero-day attacks. Here are some of the more notable ones.

2021: Chrome

Google’s Chrome browser suffered a series of zero-day threats stemming from a version 8 JavaScript engine bug.

2021: Kaseya

In July, REvil used zero-day vulnerabilities to deliver a malicious update. The attack compromised approximately 60 Kaseya customers while also affecting 1,500 downstream companies.

2021: SonicWall VPN

This zero-day vulnerability affected the company’s Secure Mobile Access (SMA) devices, including the SMA 100 series product. It required updates to SMA devices running 10. x firmware.

2020: Zoom

Hackers launched an attack that accessed a user’s PC remotely if running an older version of Windows. Consequently, they could completely take over the PC if the machine was that of an administrator.

2020: Apple iOS

Apple fell victim to at least two sets of vulnerabilities, including a bug that allowed a hacker to compromise iPhones remotely.

Identifying a Zero-Day Vulnerability

Zero-day vulnerabilities take multiple forms – SQL injection, buffer overflows, missing data encryption, missing authorizations, broken algorithms, bugs, password security, and more. And that’s what makes them challenging to detect. For that reason, vulnerabilities often go unnoticed until the exploit gets identified.

You might see increased traffic or suspicious scanning activities originating from a client or service. Detection techniques include:

• Scanning internet traffic
• Examining incoming file codes as well as the interactions with existing code
• Leveraging malware detection methods
• Machine learning by reviewing previously recorded exploits to establish a baseline for safe system behavior

Arguably, your best approach relies on user behavior analytics. Most entities authorized to access your networks, for example, exhibit specific usage and behavior patterns that are considered normal. So, any activity falling outside those normal activities could indicate the presence of a zero-day attack.

Protecting Against Zero-Day Attacks

You can reduce your risks of a zero-day attack by following cybersecurity best practices. Some key actions include:

1. System Updates: By keeping your operating systems and software current, you’ll take advantage of security patches that may cover vulnerabilities. Generally, your best approach is automating updates to ensure software gets updated routinely. Equally, the minute a patch becomes available, implement it.
2. Virtual Area Networks: A VAN segregates areas of your network, allowing you to isolate sensitive traffic.
3. IPsec: This IP security protocol applies encryption and authentication to network traffic.
4. Privileges: Assign access privileges on an as-needed basis.
5. Vulnerability Scanning: Perform regular scans against your networks and lockdown discovered vulnerabilities.
6. Streamline: Use only required software and applications. The more you have of each, the more opportunity you have for a zero-day vulnerability.
7. Firewall: It may be obvious, but a next-generation firewall sets the foundation for your cybersecurity. You can also configure it to allow only necessary transactions.
8. Antivirus Software: Another fundamental solution, antivirus software blocks known and unknown threats.
9. Cyber Awareness Training: Your employees present one of your most significant cybersecurity risks. Cybercriminals know it, so they capitalize by using social engineering tactics that can trigger zero-day exploits. Cyber awareness training educates employees about security dangers and helps promote good security habits.

Ultimately, it simply pays to stay informed about the latest risks in the threat landscape. That, in and of itself, can be daunting. So, you might want to work with a managed IT services or managed security services company.

Need Some Help Locking Down Your Cybersecurity?

The cybersecurity landscape presents a moving and growing target. It’s difficult for organizations, notably smaller and midsized ones, to stay on top of things. We can help.

Our IT company has been working with local SMBs in Harrisburg, York, Lancaster, and surrounding areas for more than 15 years now. We’ve designed our IT services to meet your needs. If you need help with cybersecurity or just IT support in general, contact us.