# Determining the OpenSSL version

> Check which OpenSSL version your server or computer runs with a single command, and why it matters for security.

Source: https://helpcenter.ruachost.com/ssl-security/ssl-certificates/determining-the-openssl-version/

**OpenSSL** is a widely used library for implementing SSL/TLS encryption. Knowing which version is installed on your server helps you verify available features and check whether your system is affected by known security vulnerabilities.

## Why Check the OpenSSL Version?

- Confirm compatibility with SSL/TLS certificates.
- Ensure your server supports modern encryption standards.
- Identify if your system is exposed to known vulnerabilities (e.g., Heartbleed).
- Plan upgrades or patches proactively.

## Checking the Version on Linux Servers

1. **Log in via SSH** to your server.
2. Run the following command:

   ```bash
   openssl version
   ```

   This displays the installed OpenSSL version (e.g., `OpenSSL 1.1.1w 11 Sep 2023`).
3. For more detailed information, run:

   ```bash
   openssl version -a
   ```

   This shows build date, platform, compiler options, and directory paths.

## Checking via WHM/cPanel

- WHM and cPanel rely on the system’s OpenSSL installation.
- To confirm the version:

  1. Log in to your server via SSH.
  2. Use the same `openssl version` command.
- WHM itself does not display OpenSSL version directly; it must be checked at the OS level.

> **Note:**
- Always keep OpenSSL updated to the latest stable release.
- Outdated versions may lack support for TLS 1.2/1.3 or contain vulnerabilities.
- For more information, visit the official OpenSSL website.