How to Investigate Suspicious URLs Like a SOC Analyst ? Top Tools & Steps Explained

Learn how to investigate suspicious URLs as a SOC Analyst using expert tools like VirusTotal, URLScan.io, and Hybrid Analysis. Understand techniques, key indicators of malicious URLs, and how to detect phishing or malware threats before they harm your network.

Penetration Testing Jun 19, 2025 14 Add to Reading List

In today’s digital threat landscape, malicious URLs are among the most commonly used weapons in phishing, malware delivery, and command-and-control (C2) operations. As a SOC (Security Operations Center) Analyst, the ability to quickly and accurately investigate suspicious URLs is a critical skill that can help prevent data breaches and system compromise.

This blog will walk you through the process of investigating URLs, introduce the top tools used in the industry, and explain how to interpret results effectively.

Why Are Suspicious URLs a Threat?

URLs can act as:

Phishing vectors – Trick users into revealing credentials.
Payload delivery points – Drop malware or scripts.
Redirects to exploit kits – Lead users to vulnerable web pages.
C2 channels – Used by malware to communicate with threat actors.

Real-World Example:

In 2024, a major financial firm was breached via a phishing email containing a shortened URL. The link redirected to a clone of their internal VPN portal and captured employee credentials, causing a 3-week disruption.

Workflow for URL Investigation as a SOC Analyst

Step	Description
1. Initial Triaging	Source of the URL, email headers, user report
2. Static Analysis	Analyze without clicking — extract domain, TLD, IP, etc.
3. Passive Lookup	Use tools to check historical records and reputation
4. Sandbox Execution	Open the URL in a safe environment (sandbox/VM)
5. Reporting	Document findings, classify risk, take action

Top Tools Every SOC Analyst Should Use for URL Investigation

1. VirusTotal

Aggregates antivirus engines and URL reputation databases.
Provides IP/domain WHOIS, detection rates, and sandboxed behavior.

2. URLScan.io

Scans the URL and presents how the page loads, domains contacted, redirects, etc.
Visual interface for DOM structure and network requests.

3. Hybrid Analysis

Lets you analyze files or URLs in a sandbox.
Good for detecting malicious behavior patterns like data exfiltration or exploit attempts.

4. Any.run

Interactive sandbox with real-time process analysis.
Especially useful when the URL drops a file or redirects to malware.

5. PhishTool

SOC-focused interface that helps analyze phishing URLs in emails.
Integrates DMARC, SPF, DKIM checks, and links to threat intel sources.

6. Google Safe Browsing

Checks if a site is reported as phishing or malware-hosting.
Built into Chrome and available via API.

7. Talos Intelligence (Cisco)

Provides WHOIS data, DNS lookups, and domain reputation.

8. ThreatCrowd / VirusBay / URLhaus

Passive threat intelligence feeds showing malicious domains and payload history.

9. Shodan

Search for exposed services or systems behind a URL/IP.

10. WhoisXML / Domaintools

Perform deep WHOIS lookup to find creation date, owner, registrar, and possible IOC links.

What to Look for When Investigating a Suspicious URL

Indicator	What It Might Mean
Random strings in subdomain	Domain generation algorithm (DGA) behavior
Recently created domain	Often linked to phishing/malware
Suspicious TLD (.tk, .xyz)	Frequently abused by threat actors
Multiple redirections	Obfuscation or payload staging
Use of IP address instead of domain	Trying to bypass filters
Shortened URLs (bit.ly)	Often used to hide the final destination

Example: Investigating a Suspicious Link

Let’s say you receive the URL: http://verify-login-alert[.]net/login.php?user=admin

Steps:

Submit to VirusTotal → Found 6 AV engines flagging it as phishing.
Scan on URLScan.io → It loads a fake Microsoft 365 login page.
Use WhoisXML → Domain registered 2 days ago from a registrar in Panama.
Sandbox in Any.run → Captures credentials and redirects to legitimate Microsoft page.

Result: Marked as phishing, added to denylist, users alerted.

✅ Best Practices for SOC Analysts

Never click URLs directly. Use curl or wget in controlled environments or sandboxes.
Correlate findings. Use multiple tools to avoid false positives/negatives.
Record every detail. Log timestamps, IPs, domain age, sandbox behavior.
Automate with SOAR. Many of these tools have APIs and integrations to automate triage.

Sample Report Template for URL Investigation

Field	Value
Suspicious URL	http://verify-login-alert[.]net
Detection Tools Used	VirusTotal, URLScan, WhoisXML
Domain Age	2 days
Malicious Behavior	Phishing – fake Microsoft login
Sandbox Result	Captures user credentials
Action Taken	Blocked domain, notified users, updated firewall rules

Final Thoughts

Investigating URLs is one of the most frequent and critical responsibilities for SOC analysts. With phishing and malware becoming more targeted and deceptive, your knowledge of the right tools and workflows can make the difference between a blocked attack and a successful breach.

Always assume the worst until proven otherwise — investigate every URL like it’s a loaded weapon.

FAQ

What is a suspicious URL?

A suspicious URL is a web address that may host phishing, malware, or redirect to malicious content and needs investigation.

How do I check if a URL is malicious?

Use online tools like VirusTotal, URLScan.io, or Hybrid Analysis to scan the URL for malicious behavior.

What tools are used by SOC analysts to investigate URLs?

Top tools include VirusTotal, URLScan.io, Any.run, Hybrid Analysis, PhishTool, Talos Intelligence, and WhoisXML.

Is VirusTotal free to use for URL scanning?

Yes, VirusTotal offers free scanning of URLs, files, and domains for reputation and threat data.

What is URLScan.io used for?

URLScan.io captures and visualizes how a URL loads, including redirects, scripts, and DNS calls.

How does Any.run help in URL investigation?

It provides a real-time sandbox where analysts can interact with the URL and watch its behavior.

What is WHOIS lookup in URL analysis?

WHOIS provides information about the domain registration, owner, and age — useful in detecting suspicious new domains.

Why do hackers use shortened URLs?

Shortened URLs (like bit.ly) are used to hide the true destination and bypass filters.

What is BOLA in API and URL context?

Broken Object Level Authorization (BOLA) allows attackers to access other users’ data by altering identifiers in URLs.

How do I analyze URLs without opening them?

Use online reputation tools or curl/wget in a secure VM; never click directly on suspicious links.

What is a redirect chain in URLs?

It’s a series of automatic redirections that could lead users from a harmless site to a malicious one.

Why is domain age important in URL investigations?

Malicious domains are often newly registered and used for quick phishing or malware campaigns.

What’s the difference between static and dynamic analysis of a URL?

Static checks metadata, structure, and DNS info; dynamic involves executing the URL in a sandbox to observe behavior.

Can Google Safe Browsing detect all phishing links?

Not all — it maintains a list of reported sites but may miss brand-new or obfuscated threats.

What’s the role of PhishTool in URL analysis?

PhishTool helps analyze email headers and embedded URLs to detect phishing attempts.

How do SOC teams automate URL investigation?

Using SOAR platforms, they integrate APIs from tools like VirusTotal and URLScan into workflows.

Can links contain malware directly?

Yes, some URLs host executable payloads or scripts that exploit browser vulnerabilities.

What is a Command-and-Control (C2) URL?

A C2 URL is used by malware to communicate with attackers and can be identified by behavior and IP reputation.

What is a passive DNS lookup?

It allows analysts to see the historical resolution of domains to IPs, helping detect rotating malicious infrastructure.

How do you investigate URLs from phishing emails?

Extract the link, scan it with reputation tools, check for redirects, and observe sandbox behavior.

Are all suspicious URLs dangerous?

Not always, but they should be treated with caution until proven safe.

What does URLHaus provide?

URLHaus is a repository of malicious URLs, especially those used to distribute malware.

Can cybercriminals mask links to look legitimate?

Yes, they often use homograph attacks or subdomain tricks to mimic legitimate domains.

How often should SOC teams update their threat intelligence?

Regularly, often hourly or daily, using feeds from security vendors and community-driven sources.

What is a sandbox in URL investigation?

A sandbox is an isolated environment where URLs can be safely executed to observe real behavior.

Is it safe to use curl or wget for URL checking?

Yes, but only in a secure environment or sandbox, as responses might trigger payloads.

How to document a URL investigation?

Include original link, reputation tool results, domain info, sandbox behavior, and final classification.

What’s an IOC in URL investigation?

IOC (Indicator of Compromise) includes malicious domains, IPs, file hashes, or patterns linked to threats.

Can a single URL compromise a network?

Yes, if it delivers malware, exploits a zero-day vulnerability, or leads to credential theft.

How does Shodan help with URL investigation?

Shodan lets you see services, banners, and exposures on the IP linked to the URL.