From VirusTotal to Bug Bounty: What I Learned from My Cybersecurity Quiz

As part of my cybersecurity learning journey, I recently completed a hands-on quiz that covered malware analysis, account security, Linux fundamentals, reconnaissance, web application security, and bug bounty basics.

Rather than simply answering questions, I had the opportunity to apply practical security concepts using real-world tools. Here are my biggest takeaways.

1. Malware Analysis with VirusTotal

One exercise involved analyzing a file hash using VirusTotal. The scan showed that 66 out of 68 security vendors detected the file as malicious.

This demonstrated the importance of verifying suspicious files with multiple antivirus engines before trusting or executing them. While no detection system is perfect, a high detection rate is a strong indicator that a file is unsafe.

2. Auditing My Google Account Security

I also reviewed my Google account's security settings.

During the audit, I confirmed that:

• Two-Factor Authentication (2FA) was enabled.
• Google Password Manager was active.

Simple security checks like these significantly reduce the risk of account compromise.

3. Investigating a Suspicious URL

Using urlscan.io, I analyzed a suspicious login URL.

Some of the red flags included:

• A suspicious-looking domain name
• DNS resolution failure
• No valid IPv4 or IPv6 address

These are common indicators that a website may be malicious or part of a phishing campaign.

4. Understanding Linux File Permissions

Running the ls -la command reminded me that:

• d indicates a directory
• • indicates a regular file

5. I also learned that after executing:

chmod 700 test.sh

Then ls -l test.sh

This is the output

only the file owner has permission to read, write, and execute the file.

Understanding Linux permissions is fundamental to securing systems.

6. Why Security Professionals Check Logs

I run 'grep "error" /var/log/syslog

This is the result

Security professionals check logs because logs are the digital record of everything that happens on a system.

7. Identifying a Web Application Vulnerability

One example involved PHP code that accepted user input directly from the URL and displayed it without validation.

. I analyzed the code below

$name = $_GET['name'];

Echo "welcome ". $name;

This code have a vulnerability which is the wrong use of http methods.

The hacker can easily change the name in the url to bring another name

This vulnerability can be fixed by replacing GET with POST.

8. Mobile App Permissions Matter

Applications requesting unnecessary permissions should always raise concerns.

For example:

• Contact permissions can expose an entire address book.
• Microphone access can create privacy risks if abused.

A hacker can use the contacts permission to harvest phone numbers in the victim's phone book and use vishing or smishing to accomplish what ever aim they want to accomplish.

9. Why Reconnaissance Is So Important

One lesson that stood out was the value of reconnaissance during bug bounty hunting.

Discovering subdomains and technologies used by a target gives a much broader view of the attack surface.

Instead of focusing only on the main website, researchers can identify additional applications, APIs, and services that may contain security weaknesses.

Similarly, collecting information such as:

• Domain registrar
• Domain creation date
• Historical website snapshots

can reveal legacy assets, hidden infrastructure, and valuable clues for further investigation.

10. Domain Intelligence

Knowing a website's registrar, creation date, and historical snapshots helps a bug bounty hunter gather valuable background information, identify hidden or legacy assets, and uncover clues that can guide further reconnaissance and vulnerability testing.

11. Bug Bounty Report

Title: Product ID showing in url

Severity: medium.

A user can access a product they're not authorized to access by changing the product ID in the url

Steps to reproduce:

1. open testphp.vulnweb.com

2. go to /product.php?id=1

3. change the id=1 to id=2

Impact: this can make a user access what they're not authorized to access therefore breaking the confidentiality of that product.

12. Severerity Justification

When a login page has no rate limit and you can try 1000 passwords per second.

The severity is high

Why: A login page with no rate limiting allows an attacker to perform brute-force or credential-stuffing attacks at a very high speed, greatly increasing the likelihood of compromising user accounts. If there are no additional protections such as MFA, CAPTCHA, or account lockout, the impact can be severely highbecause attackers can rapidly test thousands of passwords until they find valid credentials.

13. Scope And Ethics

when you find a bug on a target and the bug is within the scope of the targets bug bounty program, you can submit the bug because its within the scope

Finally, I reinforced two important ethical rules every bug bounty hunter should follow:

• Never test assets that are outside the program's defined scope.
• Never access, modify, or exfiltrate real user data while verifying a vulnerability.