Ensure there is no unrestricted inbound access to UDP port 11211 (Memcached)

Security & Compliance

Memcached is a distributed memory object caching system that is commonly used to speed up dynamic database-driven websites. It listens on UDP port 11211 by default, which can be a potential security vulnerability if the port is open and accessible to the internet without any restrictions. Attackers can exploit this port to launch various attacks, including distributed denial-of-service (DDoS) attacks or data exfiltration attacks.


Here are the steps to remediate the issue of unrestricted inbound access to UDP port 11211 (Memcached):

  1. Identify open ports: Identify any open UDP ports in your security groups or network access control lists (ACLs) that allow inbound traffic to port 11211 (Memcached).
  2. Restrict access: Restrict access to UDP port 11211 (Memcached) by modifying the security group rules and network ACLs to allow inbound traffic only from trusted sources. This can be done by adding specific IP addresses or IP address ranges to the allowed list.
  3. Implement authentication: Implement authentication mechanisms to ensure that only authorized clients can access the Memcached instance. This can be done by requiring clients to provide a username and password or using other authentication methods.
  4. Enable encryption: Enable SSL/TLS encryption to secure the communication between Memcached clients and servers. This can help to prevent eavesdropping and man-in-the-middle attacks.
  5. Monitor and update: Regularly monitor your security group rules and network ACLs for changes and update them as needed to ensure that your systems are always protected against unauthorized access through UDP port 11211 (Memcached).

By following these remediation steps, you can help to ensure that there is no unrestricted inbound access to UDP port 11211 (Memcached), which can help to prevent security breaches and protect your sensitive data.

Enforced Resources
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.