What Is HTTP 425 Too Early?

HTTP 425 Too Early explained, and what it means when you see it in CI/CD and deployments.

HTTP 425 means the server refuses to process a request that might be replayed.

What it means

A 425 relates to TLS 1.3 early data (0-RTT). The server rejects requests sent in early data to avoid replay attacks.

When you see it in CI/CD

CI rarely encounters 425 directly; it is a low-level TLS optimization concern. If seen, disable early data for that client.

Key takeaways

• 425 means too early (TLS 0-RTT).
• Protects against replay attacks.
• Disable early data if it appears.

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