Why can a VM in my GCP project not respect my authorizedNetworksConfig and access my GKE cluster?

[yemaney]

Control Plane Networking

DNS endpoint	Disabled
Control plane access using IPv4 addresses	Enabled
Public endpoint	3.1.5.1
Private endpoint	10.0.128.2
Access using control plane's internal IP address from any region	Disabled
Authorized networks	Enabled 1.1.1.1/32 (1.1.1.1/32)
Enforce authorized networks on control plane's internal endpoint	Enabled
Add Google Cloud external IP addresses to authorized networks	Disabled

curl -v -k https://3.1.5.1:443
*   Trying 3.1.5.1:443...
* Connected to 3.1.5.1 (3.1.5.1) port 443
* ALPN: curl offers h2,http/1.1
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
* TLSv1.3 (IN), TLS handshake, Server hello (2):
* TLSv1.3 (IN), TLS handshake, Encrypted Extensions (8):
* TLSv1.3 (IN), TLS handshake, Request CERT (13):
* TLSv1.3 (IN), TLS handshake, Certificate (11):
* TLSv1.3 (IN), TLS handshake, CERT verify (15):
* TLSv1.3 (IN), TLS handshake, Finished (20):
* TLSv1.3 (OUT), TLS change cipher, Change cipher spec (1):
* TLSv1.3 (OUT), TLS handshake, Certificate (11):
* TLSv1.3 (OUT), TLS handshake, Finished (20):
* SSL connection using TLSv1.3 / TLS_AES_128_GCM_SHA256 / X25519 / RSASSA-PSS
* ALPN: server accepted h2
* Server certificate:
*  subject: CN=3.1.5.1
*  start date: Mar  9 15:08:20 2026 GMT
*  expire date: Mar  8 15:10:20 2031 GMT
*  issuer: CN=42cf934c-62af-43da-a4b4-18dfde5075ff
*  SSL certificate verify result: unable to get local issuer certificate (20), continuing anyway.
*   Certificate level 0: Public key type RSA (2048/112 Bits/secBits), signed using sha256WithRSAEncryption
* using HTTP/2
* [HTTP/2] [1] OPENED stream for https://3.1.5.1:443/
* [HTTP/2] [1] [:method: GET]
* [HTTP/2] [1] [:scheme: https]
* [HTTP/2] [1] [:authority: 3.1.5.1]
* [HTTP/2] [1] [:path: /]
* [HTTP/2] [1] [user-agent: curl/8.5.0]
* [HTTP/2] [1] [accept: 
*/*
]
> GET / HTTP/2
> Host: 3.1.5.1
> User-Agent: curl/8.5.0
> Accept: 
*/*
> 
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
* received GOAWAY, error=0, last_stream=1
< HTTP/2 403 
< audit-id: 862ae066-13a9-4023-a827-1477d820af89
< cache-control: no-cache, private
< content-type: application/json
< x-content-type-options: nosniff
< x-kubernetes-pf-flowschema-uid: 4846a272-5617-4af1-a810-65f3f326d883
< x-kubernetes-pf-prioritylevel-uid: 44f8bcba-5c1b-48fa-8092-315e0d12878e
< content-length: 217
< date: Tue, 10 Mar 2026 06:22:51 GMT
< 
{
  "kind": "Status",
  "apiVersion": "v1",
  "metadata": {},
  "status": "Failure",
  "message": "forbidden: User \"system:anonymous\" cannot get path \"/\"",
  "reason": "Forbidden",
  "details": {},
  "code": 403
* Closing connection
* TLSv1.3 (OUT), TLS alert, close notify (256):
```

The vm is in the same region as the cluster but in different vpc.
I've added an authorized network of `1.1.1.1/32`.

This configuration blocks my local laptop from making kubectl connections to the cluster.
But the vm that is also running in gke can still make network connectoins to the cluster. Confirmed via curl command
```

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