Here’s How to Enhance Your Cyber Resilience with CVSS

In late 2023, the Common Vulnerability Scoring System (CVSS) v4.0 was unveiled, succeeding the eight-year-old CVSS v3.0, with the aim to enhance vulnerability assessment for both industry and the public. This latest version introduces additional metrics like safety and automation to address criticism of lacking granularity while presenting a revised scoring system for a more comprehensive evaluation. It further emphasizes the importance of considering environmental and threat metrics alongside the base score to assess vulnerabilities accurately.

Why Does It Matter?

The primary purpose of the CVSS is to evaluate the risk associated with a vulnerability. Some vulnerabilities, particularly those found in network products, present a clear and significant risk as unauthenticated attackers can easily exploit them to gain remote control over affected systems. These vulnerabilities have frequently been exploited over the years, often serving as entry points for ransomware attacks.

Vulnerability assessment systems employ predefined factors to quantify vulnerabilities’ likelihood and potential impact objectively. Among these systems, CVSS has emerged as an internationally recognized standard for describing key vulnerability characteristics and determining severity levels.

CVSS evaluates vulnerabilities based on various criteria, utilizing metrics with predefined options for each metric. These metrics contribute to calculating a severity score ranging from 0.0 to 10.0, with 10.0 representing the highest severity level. These numerical scores are then mapped to qualitative categories such as “None,” “Low,” “Medium,” “High,” and “Critical,” mirroring the terminology commonly used in vulnerability reports.

The metrics employed in determining severity are categorized into three groups:

1. Base Metrics
2. Temporal Metrics
3. Environmental Metrics

Each group provides specific insights into different aspects of the vulnerability, aiding in a comprehensive assessment of its severity and potential impact.

By utilizing Common Vulnerability and Exposure (CVE) identifiers:

• companies can effectively track known vulnerabilities across their systems, allowing them to allocate resources for patching and remediation based on the level of risk posed by each vulnerability.
• They ensure that limited resources are utilized efficiently to address critical security concerns.
• Standardization through CVSS and CVE enhances interoperability between security tools and systems, enabling more accurate detection and response to potential threats by correlating network events with known vulnerabilities.
• Integration of threat intelligence feeds into security tools is facilitated by CVSS and CVE, allowing for identifying and prioritizing threats based on their association with known CVEs.
• Knowledge of CVSS scores and CVE identifiers also enables faster and more effective incident response, with tools automatically correlating network events with relevant CVEs to provide security teams with actionable information for prompt mitigation.
• Understanding CVSS and CVE aids companies in meeting regulatory compliance requirements, enabling them to identify, prioritize, and address vulnerabilities in accordance with regulatory frameworks.

CVSS assists in assessing vulnerability severity, allowing companies to prioritize patches and mitigation efforts effectively, focusing resources on addressing critical vulnerabilities first.

Where is it Used?

Security tools like EDR benefit from regularly incorporating data sourced from reputable CVE databases. These databases furnish details regarding known vulnerabilities, including their unique CVE identifiers and corresponding CVSS scores.

1. By aligning CVEs with signatures, EDR develops rules or signatures based on CVE particulars, with each signature corresponding to a specific vulnerability identified by its CVE.
2. Upon detecting activity that matches a signature, the EDR triggers an alert.
3. Subsequently, EDRs can hinder or isolate endpoints in response to CVE-related alerts.
4. Security teams typically utilize multiple CVE databases to monitor vulnerabilities and update their security arsenal to safeguard clients against potential threats.

Result: when a novel CVE arises, the EDR solution is promptly updated with its signature, enabling preemptive blocking of zero-day attacks at the network periphery, often preceding vendor patch deployment on vulnerable systems.

While EDR and firewalls effectively obstruct attempts to exploit known CVEs, they commonly face challenges in devising generic rules and conducting behavior analysis to identify exploit attacks from emerging or unfamiliar threat vectors.

Network Detection and Response (NDR) goes beyond the typical offerings of EDR by embracing a holistic approach to cybersecurity. NDR combines the power of scoring (such as CVSS) and Machine Learning. While EDR primarily relies on signature-based detection, NDR augments this with behavior-based anomaly detection.

This allows it to identify threats from known CVEs and novel and emerging attack vectors. By analyzing deviations and anomalies, NDR detects suspicious behavior patterns even before specific signatures are available. It doesn’t solely rely on historical data but adapts to evolving threats.

More Than the Known Vulnerabilities

While EDR excels at blocking known vulnerabilities, NDR extends its capabilities to zero-day attacks and unknown threat vectors. It doesn’t wait for CVE updates but proactively identifies abnormal activities. It observes network traffic, user behavior, and system interactions. If an activity deviates from the norm, it raises alerts, regardless of whether a specific CVE is associated. NDR continuously learns from network behavior. It adapts to changes, making it effective against novel attack techniques.

Even if an attack vector hasn’t been seen before, NDR can raise alerts based on anomalous behavior. Last but not least, NDR doesn’t limit itself to endpoints. It monitors network-wide activities, providing a broader context. NDR capabilities allow it to correlate events across the entire infrastructure.

When coupled with EDR, NDR swiftly responds to threats. It doesn’t rely solely on endpoint-based rules but considers network-wide patterns.

Make it Countable!

Risk-Based Alerting (RBA) emerges as a cornerstone of cybersecurity efficiency, employing a dynamic threat detection and response approach. By prioritizing alerts according to pre-established risk levels, RBA streamlines efforts, allowing security teams to focus where they matter most, thus reducing alert volumes and optimizing resource allocation. CVSS acts as a crucial element in effective risk management, offering a standardized framework for evaluating vulnerabilities based on their severity. High-scoring vulnerabilities, indicating high exploitability or impact, demand immediate attention and robust protective measures.

The fusion of CVSS with a risk-based approach empowers organizations to identify and address vulnerabilities, strengthening their cyber defenses proactively. Understanding CVSS and CVE enhances risk assessment, aiding in resource allocation and prioritizing patching and remediation efforts.

NDR integrates risk assessment into its core functionality, so you prioritize alerts based on severity and potential impact. You can customize alert thresholds to align with their risk tolerance, ensuring relevant alerts and optimizing resource allocation while reducing noise.

When combined with NDR solutions, the effectiveness of RBA is magnified. NDR leverages continuous monitoring and machine learning algorithms to provide real-time insights into network activity, enabling swift responses to potential threats by assessing the risk associated with detected events.

NDR, ML, RBA, and CVS combined enhance security measures and risk management in the cybersecurity landscape:

• NDR’s ML algorithms enable early threat detection by analyzing behavior-based anomalies, facilitating proactive security measures.
• ML-driven insights continuously monitor network traffic and user behavior, enhancing risk assessment and allowing swift responses to potential risks.
• So, by integrating CVSS and ML, NDR provides confidence in navigating complex cybersecurity landscapes and allows for resource efficiency through streamlined alerting based on predefined risk levels.

Leveraging CVSS scores, NDR offers granular risk assessment and prioritizes alerts based on vulnerability severity, ensuring swift responses to high-severity CVE-related alerts. Organizations can tailor alert thresholds based on CVSS scores, focusing efforts on vulnerabilities above specific thresholds. Integrating CVSS scores and CVE identifiers contextualizes alerting, guiding informed decision-making during incident response and prioritizing remediation efforts based on severity.

For more guidance on integrating CVSS, download our CVSS booklet here!

Résumé

Understanding CVSS and CVE is vital for companies and security teams. Companies benefit by efficiently allocating resources based on CVE identifiers to prioritize patching and remediation. Standardization through CVSS and CVE enhances interoperability between security tools, aiding in accurate threat detection and response.

NDR, integrating CVSS and ML, surpasses EDR with behavior-based anomaly detection, identifying threats beyond known CVEs. NDR’s adaptability to evolving threats and its network-wide monitoring capabilities make it effective against zero-day attacks and unknown threat vectors. Download our CVSS booklet for more!