> For the complete documentation index, see [llms.txt](https://ahmed-tarek.gitbook.io/security-notes/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ahmed-tarek.gitbook.io/security-notes/notes/attack-vectors-by-port/whois.md).

# WHOIS

**`Default Port: 43`**

**WHOIS** is a query and response protocol that is widely used for querying databases to determine the registrant or assignee of Internet resources, such as a domain name, an IP address block, or an autonomous system.

By using the WHOIS protocol, you can gather an extensive amount of information regarding a target.

* Domain owner
* Domain Registrar
* Name Servers
* Creation Date
* Expiration Date
* Last Updated
* State and Country etc.

### Enumeration <a href="#enumeration" id="enumeration"></a>

You can gather a substantial amount of information using the WHOIS protocol.

```
whois hackviser.com
```

Python's python-whois library offers a simple way to communicate with the WHOIS protocol:

```
import whois
w = whois.whois('hackviser.com')
print(w)

print(w.status)
print(w.name)
print(w.org)
print(w.address)
```

### Attack Vectors <a href="#attack-vectors" id="attack-vectors"></a>

Even though WHOIS itself doesn't have any direct vulnerabilities, It can inadvertently lead to security breach by leaking sensitive information.

#### Information Leakage <a href="#information-leakage" id="information-leakage"></a>

Basic reconnaissance and data gathering might allow an attacker to obtain sensitive information like contact information, addresses, registered domains, and many more.

```
whois example.com
```

#### Domain Expiration <a href="#domain-expiration" id="domain-expiration"></a>

An attacker could deny the service by waiting for the domain to expire and then registering the domain for themselves.

```
whois example.com | grep "Expiry Date"
```

<br>


---

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