Vulnerability Scanner Overview | TryHackMe Write-Up

Here i want to share about my write-up for the room Vulnerability Scanner Overview ↗ (Premium Room), learn about vulnerability scanners and how they work in a practical scenario. I wrote this in 2025 and hope it is useful for learning about cybersecurity.

Task 1: What Are Vulnerabilities?#

Vulnerabilities are weaknesses in software or hardware, similar to small holes in a roof. The process of fixing these vulnerabilities is known as Patching.

What is the process of fixing the vulnerabilities called?

Patching

Task 2: Vulnerability Scanning#

The major categorizations of these scans are:

• Authenticated vs. Unauthenticated Scans: Authenticated scans require the subject host’s credentials and are more detailed. Unauthenticated scans are conducted without providing any credentials and help identify the threat surface from outside the host.
• Internal vs. External Scans: Internal scans are conducted from inside the network, while external scans are conducted from outside the network.

Which type of vulnerability scans require the credentials of the target host?

authenticated

Which type of vulnerability scan focuses on identifying the vulnerabilities that can be exploited from outside the network?

External

Task 3: Tools for Vulnerability Scanning#

Here’s some of widely used vulnerability scanners.

• Nessus: It is a proprietary software with extensive vulnerability scanning options, widely used by large enterprises. Nessus needs to be deployed and managed on-premises.
• Qualys: A subscription-based vulnerability management solution. The best thing about Qualys is that it is a cloud-based platform.
• Nexpose: A subscription-based solution that continuously discovers new assets and performs vulnerability scans. It offers both on-premises and hybrid deployment modes.
• OpenVAS: An open-source vulnerability assessment solution that offers basic features. It is beneficial for small organizations and individual systems.

Almost all vulnerability scanners offer reporting capabilities. They generate a detailed report after every scan containing a list of the vulnerabilities discovered, their risk scores, and detailed descriptions. When choosing a suitable scanner, you must consider the scope, resources, and depth of analysis.

Is Nessus currently an open-source vulnerability scanner? (Yea/Nay)

Nay

Which company developed the Nexpose vulnerability scanner?

Rapid7

What is the name of the open-source vulnerability scanner developed by Greenbone Security?

OpenVAS

Task 4: CVE & CVSS#

CVE (Common Vulnerabilities and Exposures) is a unique number given to vulnerabilities. Whenever a new vulnerability is discovered in any software application, it is given a unique CVE number as a reference and published online in a CVE database. A CVE number has the prefix “CVE”, the year it was discovered, and four or more arbitrary digits.

CVSS (Common Vulnerability Scoring System) is a score that tells the severity of a vulnerability. The CVSS score is calculated by considering multiple factors, including its impact and ease of exploitability. The severity levels as per the CVSS scores are:

• Low: 0.0-3.9
• Medium: 4.0-6.9
• High: 7.0-8.9
• Critical: 9.0-10

CVE stands for?

Common Vulnerabilities and Exposures

Which organization developed CVE?

MITRE Corporation

What would be the severity level of the vulnerability with a score of 5.3?

Medium

Task 5: OpenVAS#

OpenVAS is a complete open-source vulnerability scanner.

What is the IP address of the machine scanned in this task?

10.10.154.44

How many vulnerabilities were discovered on this host?

13

Task 6: Practical Exercise#

What is the score of the single high-severity vulnerability found in the scan?

10

What is the solution suggested by OpenVAS for this vulnerability?

Change the password of the mentioned account(s).