theharvester
theHarvester is a crucial, open-source intelligence (OSINT) gathering tool used in the early stages of a penetration test, specifically during the Footprinting and Reconnaissance phase.
Here is a comprehensive overview of theHarvester, its purpose, and its functionalities:
1. Purpose and Classification
- Role in Footprinting: theHarvester is designed for open-source intelligence gathering to determine a company's external threat landscape on the Internet. It is used in the Reconnaissance phase.
- Tool Type: It is an automated tool used to collect publicly available information.
- Source: The tool's source is identified as
https://github.com.
2. Key Information Gathering Functions
theHarvester primarily focuses on gathering information that can be leveraged for future social engineering, brute-force attacks, and other types of exploits.
| Function | Description |
|---|---|
| Harvesting Email Lists | It is used to extract email addresses related to the target domain. This capability is critical because gathered email addresses act as an important attack vector in later hacking phases, used for social engineering and brute force attacks. |
| Enumerating Employee Details | It performs enumeration on LinkedIn and other social networking sites to find employees of the target company along with their job titles. This information can be used to gather more details (such as current location and educational qualifications) and perform social engineering attacks. |
3. Technical Usage and Syntax
theHarvester harvests email lists by leveraging various public search engines, including Google, Bing, Yahoo, and Baidu.
The typical command syntax involves specifying the target domain, limiting the number of results, and designating the source (or "banner"):
- Syntax Example (for LinkedIn Enumeration):
theHarvester -d <company name> -l <number of results> -b linkedin- Example:
theHarvester -d eccouncil -l 200 -b linkedin(used to enumerate users on LinkedIn for the domaineccouncil).
- Example:
theHarvester -d bcc.gov.bd -b yahoo
- Syntax Example (for Email Harvesting):
theharvester -d <domain> -l <limit> -b <source>- Example:
theharvester -d microsoft.com -l 200 -b baidu(used to extract email addresses formicrosoft.comusing the Baidu search engine, limiting results to 200).
- Example:
theharvester -d microsoft.com -l 200 -b baidu