TLS 1.0/1.1: Website Security Risks

TL;DR

Browsing a website using TLS 1.0 or 1.1 isn’t as secure as it used to be. These older versions of the security protocol have known weaknesses that attackers can exploit, potentially allowing them to read your data or impersonate the website. You should avoid sites still using these protocols where possible.

Understanding the Risk

TLS (Transport Layer Security) is what makes websites secure – it encrypts the communication between your computer and the website’s server, protecting things like passwords and credit card details. TLS 1.0 and 1.1 were once standard, but they’ve become outdated and vulnerable.

Why are TLS 1.0/1.1 risky?

1. Known Vulnerabilities: Researchers have found several weaknesses in these versions of TLS. These aren’t just theoretical; attackers actively try to exploit them.
2. POODLE Attack (TLS 1.0): A famous attack that can decrypt parts of encrypted data, especially cookies. While mitigations exist, they aren’t always implemented correctly.
3. BEAST Attack (TLS 1.0/1.1): Another vulnerability allowing attackers to potentially decrypt communication under specific conditions.
4. Downgrade Attacks: An attacker could force your browser and the website server to use TLS 1.0 or 1.1 even if they both support newer, more secure versions.
5. Compliance Issues: Major browsers (Chrome, Firefox, Safari, Edge) have phased out support for TLS 1.0/1.1. This means these sites may display security warnings or block connections entirely in the future. PCI DSS standards also require stronger protocols.

How to Check if a Website Uses TLS 1.0/1.1

You can check this using your browser’s developer tools:

1. Chrome: Press F12 (or right-click and select ‘Inspect’). Go to the ‘Security’ tab. Look at the ‘Protocol Version’. If it shows TLS 1.0 or 1.1, be cautious.
2. Firefox: Press F12 (or right-click and select ‘Inspect’). Go to the ‘Security’ tab. Click on the padlock icon next to the website address. Look at the ‘Connection encrypted with’. If it shows TLS 1.0 or 1.1, be cautious.
3. Online Tools: Use websites like SSL Labs SSL Server Test to get a detailed report on the website’s security configuration.

What Can You Do?

1. Avoid Entering Sensitive Information: If a site uses TLS 1.0 or 1.1, avoid submitting passwords, credit card numbers, or other personal data.
2. Use Newer Browsers: Ensure you’re using the latest version of your browser (Chrome, Firefox, Edge, Safari). They automatically disable support for older protocols.
3. Contact Website Owners: If it’s a website you use regularly, let them know about the security risk and encourage them to upgrade their TLS configuration.
4. Check Browser Settings (Advanced): While most browsers handle this automatically, you can sometimes manually check if older protocols are enabled in advanced settings. Be careful when changing these settings! For example, in Firefox:

   about:config

   Search for ‘security.tls.version.min’ and ensure it’s set to at least 3 (for TLS 1.2).

5. Consider a VPN: A Virtual Private Network (VPN) can add an extra layer of security, but it won’t fix the underlying problem with the website’s TLS configuration.

What Websites Should Do

Website owners need to:

• Upgrade their Server Configuration: Enable TLS 1.2 and TLS 1.3, and disable older versions like TLS 1.0 and 1.1.
• Check Compatibility: Ensure all users can still access the site after upgrading (though support for older browsers is decreasing).
• Regular Security Audits: Regularly scan their website for vulnerabilities using tools like SSL Labs SSL Server Test.