AWS transfer high security documentation change
Summary
Updated guidance on Network Load Balancer usage with AWS Transfer Family, added TLS session resumption recommendations, and security implications of NLB configurations
Security assessment
The change adds explicit security recommendations including enforcing TLS session resumption to prevent downgrade attacks and maintain encryption standards. The documentation emphasizes security improvements through ENFORCED TLS mode and compliance considerations, directly addressing potential security weaknesses in NLB configurations.
Diff
diff --git a/transfer/latest/userguide/infrastructure-security.md b/transfer/latest/userguide/infrastructure-security.md index 8c12c3f11..dd71d7c74 100644 --- a//transfer/latest/userguide/infrastructure-security.md +++ b//transfer/latest/userguide/infrastructure-security.md @@ -26 +26 @@ We've spoken with many customers who have configured a Network Load Balancer (NL -If you're using this configuration, we encourage you to move to a VPC endpoint and use an Elastic IP. Placing an NLB in front of your AWS Transfer Family server removes your ability to see the source IP of your users, because AWS Transfer Family will see only the IP address of your NLB. This not only degrades your ability to audit who is accessing your server, it can also impact performance. AWS Transfer Family uses the source IP to shard your connections across our data plane. In the case of FTPS, this means that instead of being able to have 10,000 simultaneous connections, a AWS Transfer Family server with an NLB in front of it would be limited to only 300 simultaneous connections. +If you're using this configuration, we encourage you to move to a VPC endpoint and use an Elastic IP. Placing an NLB in front of your AWS Transfer Family server removes your ability to see the source IP of your users, because AWS Transfer Family will see only the IP address of your NLB. @@ -28 +28,26 @@ If you're using this configuration, we encourage you to move to a VPC endpoint a -If you have a use case that requires you to place an NLB in front of your AWS Transfer Family server, reach out to the AWS Transfer Family Product Management team through AWS Support, so we can look for options to help you take full advantage of our service. +If you are using the FTPS protocol, this not only degrades your ability to audit who is accessing your server, it can also impact performance. AWS Transfer Family uses the source IP to shard your connections across our data plane. In the case of FTPS, this means that instead of being able to have 10,000 simultaneous connections, a Transfer Family server with an NLB in front of it would be limited to only 300 simultaneous connections. + +While we recommend avoiding Network Load Balancers in front of AWS Transfer Family servers, if your FTP or FTPS implementation requires an NLB, follow these recommendations: + + * Use port 21 for health checks, rather than ports 8192-8200. + + * Enable TLS session resumption by setting `TlsSessionResumptionMode = ENFORCED`. + +###### Note + +This is the Recommended mode, as it provides enhanced security: + + * Requires clients to use TLS session resumption for subsequent connections. + + * Provides stronger security guarantees by ensuring consistent encryption parameters. + + * Helps prevent potential downgrade attacks. + + * Maintains compliance with security standards while optimizing performance. + + * If possible, migrate away from using an NLB to take full advantage of AWS Transfer Family performance and connection limits. + + + + +For additional guidance on NLB alternatives, contact the AWS Transfer Family Product Management team through AWS Support. For more details on improving your security posture, see the blog post [Six tips to improve the security of your AWS Transfer Family server](https://aws.amazon.com/blogs/security/six-tips-to-improve-the-security-of-your-aws-transfer-family-server/).