TLDR: Misconfigured IPv6 setups can lead to security vulnerabilities, network performance issues, and operational disruptions. Common examples include improperly implemented access control lists (ACLs), failure to disable unused IPv6 interfaces, and incorrect configuration of DNS records for IPv6 addresses. These issues may expose networks to unauthorized access, man-in-the-middle attacks, or traffic routing problems, undermining the benefits of transitioning to IPv6 introduced in 1998.
https://en.wikipedia.org/wiki/IPv6
One of the primary challenges with misconfigured IPv6 networks is the lack of visibility and understanding of its unique features, such as address autoconfiguration and the vastly expanded address space. For instance, failing to configure firewalls to account for both IPv4 and IPv6 traffic can result in open IPv6 ports that bypass security measures. Additionally, incorrectly implementing features like IPv6 multicast or neighbor discovery can lead to network instability and increased attack surfaces, such as RA spoofing attacks.
https://datatracker.ietf.org/doc/rfc8200/
To mitigate risks associated with IPv6 misconfiguration, organizations must adopt a structured approach to deployment and management. This includes disabling unused IPv6 interfaces, ensuring that ACLs and firewalls are configured correctly for dual-stack environments, and conducting regular security audits. Leveraging tools like Wireshark or Nmap (with IPv6 support introduced in 2010) can help identify misconfigurations and vulnerabilities in the IPv6 infrastructure. Training IT staff on IPv6 intricacies and potential pitfalls is also critical to a secure and efficient deployment.