Server Certificate Validation Through OCSP Stapling

SSL Certificates are data files that bind a cryptographic key. There are servers that uses vulnerable versions of openSSL. This may lead to OCSP stapling vulnerability. The old versions of OpenSSL allow remote attackers to successfully attempt a denial of service. The attacker can also possibly get sensitive information in a web application. This can be done by using a vulnerable/improper ClientHello handshake message. This message will trigger out-of-bounds memory access.

Impact

The impact include:-

• Denial of service
• OCSP Stapling

Mitigation / Precaution

This vulnerability can be fixed by:-

• Updating the OpenSSL to Latest version
• Upgrading the version
• If it is not immediately possible, patch the source code for OCSP Stapling

Written by

Jijith Rajan

Cyber Security Engineer