SSL Lookup

SSL Lookup FAQ

What is SSL Lookup?

SSL Lookup is a process used to verify the details and validity of an SSL (Secure Sockets Layer) certificate. It involves querying the SSL certificate of a website to gather information such as the issuer, expiration date, and the level of encryption used. This is crucial for ensuring the security of data transmitted between the user and the website.

Why is SSL Lookup important?

SSL Lookup is important because it helps to:

  1. Verify the authenticity of a website: Ensuring the website is legitimate and not a phishing site.
  2. Ensure data security: Confirming that the data transmitted is encrypted and secure.
  3. Check certificate validity: Monitoring the expiration date to prevent lapses in security coverage.
  4. Identify potential security risks: Detecting issues like mismatched domain names or revoked certificates.

How do you perform an SSL Lookup?

Performing an SSL Lookup can be done through various methods:

  1. Online tools: Websites like SSL Labs' SSL Test or Why No Padlock provide comprehensive SSL certificate details.
  2. Browser inspection: Most browsers allow users to view SSL certificate information by clicking on the padlock icon in the address bar.
  3. Command line tools: Using commands like openssl s_client -connect in the terminal to manually inspect SSL certificates.

What information can be obtained from an SSL Lookup?

An SSL Lookup can provide detailed information such as:

  • Issuer: The Certificate Authority (CA) that issued the certificate.
  • Subject: The entity to which the certificate was issued, typically the website's domain.
  • Validity period: Start and expiration dates of the certificate.
  • Encryption details: Information about the encryption algorithms and strength used.
  • SAN (Subject Alternative Name): Additional domains covered by the certificate.
  • CRL (Certificate Revocation List): Indicating if the certificate has been revoked.

What are the common issues detected during an SSL Lookup?

Common issues that can be detected during an SSL Lookup include:

  1. Expired certificates: Certificates that have passed their validity period.
  2. Mismatched domain names: When the certificate's domain does not match the website's domain.
  3. Revoked certificates: Certificates that have been revoked by the CA.
  4. Weak encryption algorithms: Use of outdated or insecure encryption methods.
  5. Untrusted issuer: Certificates issued by an untrusted or unknown CA.

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