TLS vs SSL: differences and weaknesses

In today’s digitally interconnected world, maintaining secure communication between users and websites is crucial. The primary technologies that enable secure communication are SSL (Secure Socket Layer) and TLS (Transport Layer Security). SSL and TLS are cryptographic protocols that encrypt data sent over the internet, protecting sensitive information from unauthorised access. In this blog, we will look into the basic differences between TLS and SSL.

SSL and TLS are protocols for secure internet communication. TLS is the successor of SSL, which means SSL came way before TLS, and TLS was intended to address some of SSL's vulnerabilities and weaknesses.

The basic key differences between SSL and TLS are as follows:

1. Encryption

TLS uses strong encryption algorithms such as 3DES or AES, whereas SSL uses 128-bit encryption, which is inferior to what TLS provides.

2. Compatibility

TLS is the successor to SSL, and it is compatible with systems that previously supported SSL. SSL, on the other hand, cannot communicate with or work with TLS-enabled systems.
1. As a result, upgrading to TLS is an excellent choice. Also, tls v1.3 is a good option, as tls1.0 and tls1.1 have already reached the end of the life.

3. Certificate verification

SSL and TLS verify certificate authenticity using different methods. SSL only checks that the certificate is signed by a trusted certificate authority, whereas TLS checks that the certificate is not expired, has not been revoked, and matches the requested domain name.

4. Handshake Process

The handshake process for establishing a secure connection varies slightly between SSL and TLS, with TLS having more robust key exchange algorithms.

5. Cipher Suites

TLS supports newer and stronger cipher suites than SSL, providing better encryption and authentication methods.

Note:

Security:

TLS is widely believed to be more secure than SSL. SSL has known vulnerabilities, including POODLE and Heartbleed, which have been exploited in the past. TLS has better security features and is less prone to attacks.

Some of the vulnerabilities are as follows:

1. Heartbleed Bug

The Heartbleed bug allows anyone on the Internet to read the memory of systems that are protected by vulnerable OpenSSL software. This compromises the secret keys used to identify service providers and encrypt traffic, as well as the users’ names, passwords, and content.

More information: Heartbleed bug, simple yet dangerous

2. POODLE

POODLE stands for “Padding Oracle On Downgraded Legacy Encryption”. In this vulnerability, an attacker is Man-in-the-Middle (MiTM) first.

Downgrade the TLS connection to SSLv3.
If the cypher suite employs an RC4 or Block cypher in CBC mode, the attacker can retrieve partial bytes of encrypted text and later obtain full plain text.

More information: POODLE Attack Explained, CVE-2014–3566 — NVD

Conclusion:

To summarise, TLS is a newer and more secure protocol than SSL, featuring stronger encryption algorithms and improved certificate verification. For secure internet communication, it is recommended to use TLS rather than SSL.

#cybersecurity #TLS #SSL #heartbleed #openssl #POODLE #vulnerabilites