What Is a Zero Day Attack?
Zero-day vulnerabilities are among the most common attacks, and possibly the most difficult to defend against. They occur when hackers exploit vulnerabilities before software developers find a fix—hence the term “zero day”—the day before a fix or security patch is released.
Zero-day vulnerabilities can take almost any form, and can manifest as almost every type of software vulnerabilities. For example, it can take the form of data encryption failure, SQL injection, misconfiguration, buffer overflow, weak authentication, URL redirection, or ineffective password challenge.
This variability makes it difficult to proactively find zero-day vulnerabilities. This means that these vulnerabilities are difficult to effectively prevent. However, techniques and tools do exist that can reduce the organization’s threat surface and make it easier to detect and stop zero day attacks.
How Do Zero-Day Exploits Occur?
Security researchers identified seven points in time that define the scope of a zero-day attack:
- Vulnerability introduced—vulnerable code is included as part of a software application or distributed by software users.
- Exploit released—code is available that allows attackers to exploit vulnerable systems.
- Vendor discovery—the software vendor is aware of the vulnerability, but a patch is not yet available.
- Vulnerabilities publicized—vendors or security researchers post vulnerabilities online to make them widely known to users, but this also makes them known to attackers.
- Publishing antivirus signatures—if an attacker creates zero-day malware, antivirus vendors can identify and block that signature relatively quickly. This can at least block some ways attackers can exploit the vulnerability.
- Patch released—vendors will eventually release fixes for vulnerabilities. This can take anywhere from a few hours to several months depending on the complexity of the fix and its priority in the vendor's development process.
- Patch distribution complete—even after a patch is released, it may take time for users to deploy it. Organizations may not have a structured process for patch management and distribution, and home users may ignore software update notifications.
The window of exposure in which a system may be vulnerable is defined as the entire period from 1 to 7. A zero-day attack can occur between steps 2 and 4. This is the most dangerous time—when an attacker becomes aware of the vulnerability but users are unaware.
Subsequent attacks can occur even after the zero-day. Disclosure of vulnerabilities sets off a race between attackers, vendors, and users. Attackers are more likely to be successful if they reach affected systems before antivirus software is updated or patches are deployed.
What is XDR (Extended Detection and Response)?
XDR is a SaaS-based threat detection and incident response technology that reduces complexity and cost of security operations, by integrating multiple security products into a unified platform.
XDR is a tool that pulls data from the entire IT environment (both on-premises and in the cloud) to provide a clearer picture of what's happening on the network. It reduces the number of low-quality false positive alerts by correlating event information from different data streams, and combining it with external threat intelligence feeds and contextual data. At the same time, it can detect known and unknown attacks in real time.
XDR also uses proactive technologies, such as machine learning and behavioral analytics, to identify potential new or complex threats and trigger automated security responses.
Reducing the Blast Radius of Zero-Days with Zero Trust and XDR
Responding to zero-day threats requires the collaboration of multiple teams within an organization:
- Vulnerability managers should identify all affected systems and patch their software where possible.
- Threat hunters need to scrutinize comprehensive data gathered from across the environment for signs of compromised assets.
- Security engineers need to monitor exploits, virtually block them, and patch exposed systems.
These teams need multiple tools to detect vulnerable software, prevent attacks, and detect and respond to malicious activity in both on-premises and cloud environments.
How a zero trust security approach can help
A zero trust strategy can help protect organizations from breaches, including those caused by zero-day attacks. Zero trust is an approach to cybersecurity that removes implicit trust and focuses on continuous verification of user identities, devices, access, and transactions.
Zero trust is based on the principle of "never trust, always verify," and relies on multiple layers of security to protect users and applications, including network segmentation, strong authentication, and threat prevention. All of these layers help limit the blast radius of zero-day attacks. However, XDR technology in particular allows teams to quickly respond to zero-day threats.
XDR boosts zero-day response
XDR is the secret sauce that simplifies responding to zero-day vulnerabilities and reduces the risk of a successful attack. This is because XDR tools use cross-data analysis and machine learning to detect covert threats and accelerate investigations with cross-data insights.
If there are zero-day vulnerabilities, the XDR tool can help find and protect the vulnerable software. XDR tools are often able to identify known vulnerable software through their vulnerability assessment capabilities. They can also retrieve hashes associated with vulnerable software applications and libraries.
Even if it is not possible to detect the vulnerability or known exploits, XDR solutions can use behavioral analytics to detect post-exploit activity such as lateral movement and exfiltration. Threat hunters can search all XDR data including network, cloud, endpoint and identity data for signs of compromise.
Perhaps most importantly, XDR agent software installed on endpoints proactively blocks zero-day attacks, for example, by identifying abnormal processes that consume too many system resources or attempt to encrypt files. The ability to block zero-day attacks early in the exploit phase prevents further infection and damage. It also blocks post-exploit activities such as attempts to download or run malware on endpoints.
Conclusion
In conclusion, while XDR cannot completely prevent zero-day attacks, it can significantly reduce the impact of these types of attacks by providing a more comprehensive and proactive approach to cybersecurity.
By integrating and analyzing data from multiple sources, XDR can help security teams to identify and prioritize threats, and to take appropriate action to mitigate them. This can help to reduce the risk of data breaches and other types of attacks, even if a zero-day vulnerability is exploited.
Additionally, adopting a zero trust approach can further enhance an organization's defenses against zero-day attacks by limiting the attack surface and making it more difficult for hackers to gain access to sensitive resources. Overall, while zero-day attacks can be difficult to defend against, organizations can significantly reduce their risk by implementing XDR and zero trust security measures.
Author’s Bio;
Gilad David Maayan is a technology writer who has worked with over 150 technology companies including SAP, Samsung NEXT, NetApp and Imperva, producing technical and thought leadership content that elucidates technical solutions for developers and IT leadership.
