Cross transit connectivity being allowed by Lambda means that Lambda functions are able to communicate with resources in different subnets or VPCs, which can potentially increase the attack surface and create security vulnerabilities. Lambda functions can be configured to run within a VPC, which provides an additional layer of network security. However, if the Lambda function is configured to run outside of the VPC, it may be able to communicate with resources in other subnets or VPCs.
To remediate the issue of cross transit connectivity being allowed by Lambda, the following steps can be taken:
- Configure Lambda functions to run within a VPC whenever possible. This will limit network access to only the resources that are needed for the function to execute.
- Ensure that the VPC configuration is properly secured with appropriate security groups, network access controls, and routing rules.
- Configure Lambda functions to use private IP addresses for communication within the VPC, and restrict traffic between subnets and VPCs to only authorized sources and destinations.
- Implement network segmentation and least privilege access controls to further reduce the risk of unauthorized access and data exfiltration.
- Regularly review and audit network configurations to identify and remediate any security vulnerabilities.
- Consider using additional security measures such as encryption, access logging, and intrusion detection and prevention systems to further enhance the security of Lambda functions and the VPC environment.
- Train personnel on best practices for securing Lambda functions and VPCs, and ensure that all security policies and procedures are documented and followed.
Note: Remediation steps provided by Lightlytics are meant to be suggestions and guidelines only. It is crucial to thoroughly verify and test any remediation steps before applying them to production environments. Each organization's infrastructure and security needs may differ, and blindly applying suggested remediation steps without proper testing could potentially cause unforeseen issues or vulnerabilities. Therefore, it is strongly recommended that you validate and customize any remediation steps to meet your organization's specific requirements and ensure that they align with your security policies and best practices.