Developed initially as Secure Sockets Layer (SSL) protocol, Transport Layer Security (TLS) is an updated cryptographic protocol used to establish a secure and encrypted communications channel between clients and servers.
There are currently four versions of the TLS protocol—TLS 1.0, 1.1, 1.2 and 1.3 (latest)—but older versions, TLS 1.0 and 1.1, are known to be vulnerable to a number of critical attacks, such as POODLE and BEAST.
Since TLS implementation in all major web browsers and applications supports downgrade negotiation process, it leaves an opportunity for attackers to exploit weaker protocols even if a server supports the latest version.
All Major Web Browsers Will Remove TLS 1.0 and TLS 1.1 Support in 2020
According to the press releases published by four major companies, Google, Microsoft, Apple and Mozilla, their web browsers will completely drop TLS 1.0 and 1.1support by default in the first half of 2020.
TLS 1.2, which was released ten years ago to address weaknesses in TLS 1.0 and 1.1, has enjoyed wide adoption since then, and will thus be the default TLS version unless the availability of TLS 1.3, which is currently in the development stage.
According to Microsoft, as TLS 1.0 continues to age, many websites have already moved to newer versions of the protocol. Today 94 percent of sites already support TLS 1.2, while only less than one percent of daily connections in Microsoft Edge are using TLS 1.0 or 1.1.
"Two decades is a long time for a security technology to stand unmodified. While we aren't aware of significant vulnerabilities with our up-to-date implementations of TLS 1.0 and TLS 1.1, vulnerable third-party implementations do exist," Microsoft writes.Apple also says TLS 1.2 is the standard on its platforms and represents 99.6 percent of TLS connections made from Safari, while TLS 1.0 and 1.1 account for less than 0.36 percent of all connections.
"Moving to newer versions helps ensure a more secure web for everyone. Additionally, we expect the IETF to formally deprecate TLS 1.0 and 1.1 later this year, at which point protocol vulnerabilities in these versions will no longer be addressed by the IETF."
Google could not agree more and says that today only 0.5 percent of HTTPS connections made by Chrome use TLS 1.0 or 1.1.
All the tech companies recommended websites that do not support TLS 1.2 or newer to move off of the old versions of the protocol as soon as possible and is practical.
Furthermore, the PCI Data Security Standard (PCI DSS) compliance also requires websites to disable SSL/TLS 1.0 implementation by June 30, 2018.
Besides these tech giants, Gitlab today also announced to deprecate support for TLS 1.0 and TLS 1.1 on its website and API infrastructure by the end of 2018.
You can also manually disable older TLS versions on Google Chrome by opening Settings → Advanced Settings → Open Proxy Settings → Click 'Advanced' Tab → Under 'Security' section uncheck TLS 1.0 and 1.1 and then save.