Kubernetes is one of those things that’s both incredible and incredibly frustrating. It’s like discovering a futuristic spaceship in your garage—powerful, sleek, and game-changing—but realizing the user manual is missing half the pages. That hasn’t stopped its explosive adoption. Over 60% of enterprises now run Kubernetes, and that number is projected to hit 90% by 2027. The market for Kubernetes-related tech is expected to reach $10.7 billion by 2031, proving that it’s not just popular—it’s the backbone of modern infrastructure.
But popularity doesn’t equal simplicity. 97% of organizations rely on Kubernetes for data-heavy workloads, yet ask any engineer, and they’ll tell you: deploying applications is easy—securing and managing their networking? That’s the real nightmare.
Networking in Kubernetes: layers upon layers
Kubernetes abstracts away infrastructure, which is great—until you need to understand how network traffic actually flows inside your cluster. Unlike traditional networking, where you have clear IPs, subnets, and firewalls, Kubernetes networking is:
- Dynamic – Pods come and go, and so do their IP addresses.
- Multi-layered – There’s pod-to-pod, service-to-service, and ingress/egress traffic to worry about.
- Difficult to observe – Ever tried debugging a microservice failing for mysterious reasons? It’s probably a networking issue.
So why is this such a problem?
The big security vulnerabilities in Kubernetes networking
Misconfigurations, over-permissive access, and exposed endpoints can turn a single mistake into a serious breach. Let’s break down the biggest risks teams face when securing Kubernetes networking.
1. Lateral movement: Attackers love it here
Once an attacker gets a foothold in your cluster, they can move sideways between pods, services. By default, Kubernetes doesn’t enforce network isolation between pods, meaning a single compromised pod can turn into a full-blown security breach.
A real-world example? Recent research shows 1.4 million Kubernetes clusters exposed on the public internet. Many of these clusters have weak or misconfigured security, making them easy targets. Attackers scanning the internet for vulnerable clusters don’t even need to break into your infrastructure first—they can start directly at the API. If you wouldn’t expose a database without protection, why are so many Kubernetes control planes sitting out in the open?
2. No granular egress access controls
Ever looked at a Kubernetes cluster and thought, Where exactly is this traffic going? While Kubernetes does support egress filtering through NetworkPolicies, these policies can be tricky to configure correctly. Service meshes can help by adding fine-grained traffic control, observability, and encryption, but they also introduce additional operational complexity that not every team wants to manage. Many clusters still allow overly permissive outbound traffic by default, meaning if a compromised pod can make external requests, it might be exfiltrating data before you even realize it.
3. Lack of runtime network protection
You can set up all the best policies at deployment time, but if you don’t have real-time protection, an attack could be actively happening right now while your cluster happily allows traffic.
So, how do we make network troubleshooting in Kubernetes easier?
Kubernetes networking is hard, but there are ways to make network troubleshooting within it easier. Here’s a high-level approach:
- Use namespace isolation and microsegmentation – Limit which pods can talk to each other.
- Lock down egress traffic – Only allow outbound traffic to approved destinations.
- Adopt a better networking model – This is where mesh networking and VPN alternatives such as Tailscale’s Kubernetes operator provide better connectivity between your Kubernetes clusters. (Which, by the way, we’ll cover in the next post.)
This is where modern networking approaches, like mesh VPNs and software-defined connectivity, can help.
We asked solutions engineer Lee Briggs to help demystify the black box of Kubernetes networking in this on demand webinar. In it, he shows you how to secure access to your Kubernetes control plane and enable simpler cluster networking. Why? So instead of managing endless network policies and struggling with Kubernetes-native solutions that weren’t built for human sanity, you can make networking simple, secure, and seamless!
That’s exactly what we’ll talk about in the next post: How mesh VPNs fix Kubernetes networking. Stay tuned!
Will Moore
