Summary
Disabling TLS 1.0/1.1 enhances email security by addressing known vulnerabilities, but it may cause compatibility issues with older systems that don't support TLS 1.2 or higher. While most outbound traffic uses TLS 1.2 or higher, a portion still relies on older versions or transmits in clear-text. Upgrading to TLS 1.2/1.3 is strongly recommended and, in some cases, required for compliance (e.g., PCI). Implementing MTA-STS/DANE can further improve security, requiring validated TLS 1.2 connections. Configuration guides are available to assist with disabling older protocols and enabling newer ones. It is crucial to monitor connection logs, test configurations, and communicate changes to users, especially those using older email clients. Consider also STARTTLS and SMTP Authentication for secure connections. Ensure servers are configured to negotiate the highest TLS version possible, keeping in mind that incorrectly configured MTA-STS policies can lead to deliverability issues. Prioritize security best practices and assess the impact on older systems before disabling TLS 1.0/1.1.
Key findings
- Security Improvement: Disabling TLS 1.0/1.1 removes security vulnerabilities associated with older protocols.
- Compatibility Issues: Older systems that do not support TLS 1.2 or higher may experience connection failures.
- Encryption Usage: The majority of email traffic uses TLS 1.2+, but a small percentage may still rely on older versions or transmit in clear-text.
- Compliance Requirements: Disabling TLS 1.0/1.1 is necessary for some compliance standards (e.g., PCI).
- MTA-STS/DANE Benefits: Implementing MTA-STS/DANE enhances transit security by requiring validated TLS 1.2 connections.
- STARTTLS Functionality: STARTTLS upgrades unencrypted connections to encrypted ones on the same port, supporting opportunistic TLS.
- Deprecation: TLS 1.0 and 1.1 are officially deprecated and considered obsolete.
Key considerations
- Monitoring and Logging: Monitor connection logs to identify systems still using older TLS versions.
- Testing Configurations: Test different configurations to ensure compatibility and avoid disruptions.
- User Communication: Communicate changes to users, especially those using older email clients.
- Alternative Security Measures: Consider implementing STARTTLS and SMTP Authentication for secure connections.
- MTA-STS Configuration: Properly configure MTA-STS policies to avoid deliverability issues.
- Upgrade Planning: Plan for upgrading older systems to support TLS 1.2 or higher.
- Negotiation Settings: Ensure servers are configured to negotiate the highest TLS version possible.
- Impact Assessment: Carefully assess the impact on older systems before disabling TLS 1.0/1.1.
What email marketers say
11 marketer opinions
Disabling TLS 1.0/1.1 enhances security but may cause compatibility issues with older systems. While most outbound traffic uses TLS 1.2 or higher, some older systems still rely on older protocols or transmit in clear-text. Upgrading to TLS 1.2/1.3 is recommended, along with considering MTA-STS/DANE for better security. Monitoring connection logs, testing configurations, and communicating changes to users are essential. It's also important to consider STARTTLS and SMTP Authentication for secure connections.
Key opinions
- Security Improvement: Disabling TLS 1.0/1.1 improves email security by removing known vulnerabilities.
- Compatibility Issues: Older systems that do not support TLS 1.2 or higher may experience connection failures.
- Encryption Usage: Most email traffic uses TLS 1.2+, but a small percentage still uses older versions or transmits in clear-text.
- MTA-STS/DANE: Adopting MTA-STS/DANE enhances transit security and requires validated TLS 1.2 connections.
- PCI Compliance: Disabling TLS 1.0/1.1 is often a requirement for PCI compliance.
Key considerations
- Monitoring: Monitor connection logs to identify systems still using older TLS versions.
- Testing: Test different configurations to ensure compatibility and avoid disruptions.
- Communication: Communicate changes to users, especially those using older email clients.
- Alternatives: Consider implementing STARTTLS and SMTP Authentication for secure connections alongside TLS upgrades.
- MTA-STS Impact: Be aware that incorrectly configured MTA-STS policies can lead to deliverability issues.
Marketer view
Email marketer from cPanel Forums shares that disabling older TLS versions is a good security practice, but it's crucial to ensure that the server and client configurations support newer versions. They suggest testing different configurations to ensure compatibility and avoiding disruption to email services.
22 Apr 2024 - cPanel Forums
Marketer view
Marketer from Email Geeks shares that based on surveys, disabling TLS 1.0/1.1 will result in some clear-text transmissions from older systems. He also states that >97% of outbound was TLSv1.2 and most of the rest was clear-text.
19 Mar 2022 - Email Geeks
What the experts say
3 expert opinions
Enabling TLS is crucial for securing email. Modern systems should use TLS 1.2 or higher to avoid security vulnerabilities. STARTTLS upgrades unencrypted connections to encrypted ones on the same port, supporting opportunistic TLS. Servers should be configured to negotiate the highest TLS version possible.
Key opinions
- TLS Importance: Enabling TLS is a critical step for securing email domains.
- TLS Versions: Modern systems should use TLS 1.2 or higher to avoid security vulnerabilities.
- STARTTLS Function: STARTTLS upgrades unencrypted connections to encrypted (TLS) connections on the same port.
Key considerations
- Negotiation: Servers should be configured to negotiate the highest TLS version possible.
- Opportunistic TLS: STARTTLS is important for opportunistic TLS, where encryption is used if available.
Expert view
Expert from Spam Resource explains that STARTTLS is a protocol command that upgrades an unencrypted connection to an encrypted (TLS) connection on the same port, instead of switching to a different port. It's important for opportunistic TLS, where encryption is used if available but not required.
10 Nov 2023 - Spam Resource
Expert view
Expert from Word to the Wise explains that ensuring your domains send secure email is of the utmost importance and one of those steps is to ‘enable TLS’.
27 Sep 2022 - Word to the Wise
What the documentation says
4 technical articles
TLS 1.0 and 1.1 are obsolete and deprecated. The main implication of disabling them is potential connection failures for older systems that don't support TLS 1.2 or higher. The recommended solution is to upgrade systems to TLS 1.2/1.3. Configuration guides are available to technically implement the disabling of older protocols and enabling newer ones, focusing on security best practices.
Key findings
- Deprecation: TLS 1.0 and 1.1 are deprecated and considered obsolete.
- Compatibility: Disabling older TLS versions may cause connection failures with older systems.
- Upgrade Required: Upgrading systems to TLS 1.2 or higher is strongly advised and often required.
- Configuration Guidance: Detailed guides are available to configure servers for TLS 1.2/1.3 and disable older versions.
Key considerations
- Implementation: Follow technical documentation to properly implement disabling older protocols.
- Impact Assessment: Assess the impact on older systems before disabling TLS 1.0/1.1.
- Security: Prioritize security best practices when configuring TLS settings.
Technical article
Documentation from datatracker.ietf.org details that TLS 1.0 and 1.1 are considered obsolete and should be avoided. Systems should upgrade to TLS 1.2 or 1.3 to ensure secure communications. This is not an alternative but strong advice.
29 Apr 2022 - datatracker.ietf.org
Technical article
Documentation from Microsoft Docs explains that they are deprecating TLS 1.0 and 1.1 in Exchange Online. The impacts include potential connection failures for older email clients and operating systems that do not support TLS 1.2 or higher. As an alternative, users must update their systems to support TLS 1.2 or higher.
21 Sep 2022 - Microsoft Docs
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