IP Allowlisting is a security control that restricts API access to requests originating from pre-approved IP addresses or CIDR ranges.
IP Allowlisting
IP Allowlisting is a security control that restricts API access to requests originating from pre-approved IP addresses or CIDR ranges.
Why It Matters
Even if an API key is compromised, IP allowlisting ensures it can only be used from authorized networks. This is a critical defense-in-depth layer — the 2024 IBM breach report found that breaches involving stolen credentials cost an average of $4.81 million.
How It Works
The API gateway or proxy maintains a list of allowed IP addresses/ranges. Incoming requests are checked against this list before authentication is processed. Requests from non-allowed IPs are rejected with a 403 status.
Best Practices
- Allow the narrowest possible IP ranges
- Include CI/CD runner IPs if they make API calls
- Combine with other controls (rate limiting, token scoping)
- Review and update allowlists when infrastructure changes
Common Mistakes
- Allowlisting 0.0.0.0/0 (defeats the purpose)
- Forgetting to update the list when office IPs change
- Not accounting for developer VPN and remote work IPs
How ShieldKey Helps
ShieldKey's per-token IP restrictions let you set different allowed IPs for each Shield Token. Remote developers, office workers, and CI/CD runners each get their own scoped access.
Try ShieldKey FreeFAQ
Does IP allowlisting work for remote teams?
Yes, but it requires managing VPN egress IPs or using per-developer CIDR ranges. ShieldKey supports per-token IP restrictions, so each team member can have their own allowlist.