Vulnerability Impact Assessment

TL;DR

This guide shows you how to work out how badly a technical problem (a vulnerability) could hurt your business. We’ll cover finding the potential damage, working out the chance of it happening, and then putting a value on the overall risk.

1. Identify the Vulnerability

First, you need to know exactly what the problem is. This usually comes from security scans or reports. Understand:

• What’s affected: Which systems, applications, or data are vulnerable?
• How it can be exploited: What does an attacker need to do to take advantage of this vulnerability?
• Severity score: Tools like CVSS (Common Vulnerability Scoring System) give a number. Higher numbers mean more serious. Don’t rely *only* on the score; context matters!

2. Determine Potential Business Impact

This is about figuring out what could go wrong if the vulnerability is exploited. Think in terms of your business, not just technical details.

1. Data Breach: Could sensitive customer data be stolen? What regulations apply (e.g., GDPR)?
2. Service Disruption: Could a key system go down? How long would it take to fix?
3. Financial Loss: Would you lose money directly (e.g., fraud) or indirectly (e.g., lost sales)?
4. Reputational Damage: Would your customers lose trust in you?
5. Legal/Compliance Issues: Could you face fines or lawsuits?

For each impact, try to estimate a cost. This can be tricky, but even rough numbers are useful.

3. Calculate Financial Impact

Let’s get specific with the money side of things. Here are some examples:

• Data Breach: Cost per record stolen (including notification costs, legal fees, credit monitoring). Multiply by the estimated number of records at risk.
• Service Disruption: Lost revenue per hour of downtime multiplied by the estimated downtime. Also include any penalties for failing Service Level Agreements (SLAs).
• Financial Loss: Direct losses from fraud or theft.
• Reputational Damage: This is harder to quantify, but consider potential loss of customers and future revenue. A conservative estimate is better than nothing.
• Legal/Compliance Issues: Potential fines and legal costs.

Example:

Data Breach Cost = 10 GBP per record * 5,000 records = 50,000 GBP

4. Assess the Likelihood of Exploitation

How likely is it that someone will actually take advantage of this vulnerability? Consider these factors:

• Exploit Availability: Is there publicly available code to exploit the vulnerability?
• Attacker Motivation: Is your business a likely target for attackers? (e.g., do you handle valuable data?)
• Security Controls: What security measures are already in place to prevent exploitation? (e.g., firewalls, intrusion detection systems)
• Vulnerability Age: Older vulnerabilities are more likely to be exploited.

Assign a likelihood score (Low, Medium, High). You can use a simple scale:

• Low: Very unlikely; strong security controls in place.
• Medium: Possible; some security controls in place but potential for exploitation exists.
• High: Likely; weak or no security controls, exploit is publicly available.

5. Calculate Risk Value

Now combine the impact and likelihood to get a risk value.

A simple formula:

Risk Value = Impact Cost * Likelihood Score

You can use a more detailed matrix (example):

| | Low Impact | Medium Impact | High Impact |
|—————–|————|—————|————-|
| **Low Likelihood** | Low Risk | Low-Medium Risk | Medium Risk |
| **Medium Likelihood**| Low-Medium Risk | Medium Risk | High Risk |
| **High Likelihood**| Medium Risk | High Risk | Critical Risk |

6. Prioritize Remediation

Focus on the highest risk vulnerabilities first. This means fixing problems with high impact *and* high likelihood.

• Patching: Apply security updates to fix known vulnerabilities.
• Configuration Changes: Adjust system settings to improve security.
• Security Controls: Implement or strengthen existing security measures (e.g., firewalls, intrusion detection).

Document everything! Keep records of identified vulnerabilities, impact assessments, and remediation efforts.

7. Ongoing Monitoring

This isn’t a one-time task. Regularly scan for new vulnerabilities and reassess the risk associated with existing ones. cyber security is an ongoing process.