HTTP

HTTP 425 Too Early vs 525 SSL Handshake Failed

HTTP 425 (Too Early) is a 4xx Client Error response, while 525 (SSL Handshake Failed) is a 5xx Server Error response. 425 indicates that the server is unwilling to risk processing a request that might be replayed. Used with TLS 1.3 early data (0-RTT). In contrast, 525 means that cloudflare-specific. SSL/TLS handshake with the origin server failed.

Description

The server is unwilling to risk processing a request that might be replayed. Used with TLS 1.3 early data (0-RTT).

When You See It

When a server rejects a request sent as TLS 1.3 early data due to replay risk.

How to Fix

Retry the request after the TLS handshake completes.

Description

Cloudflare-specific. SSL/TLS handshake with the origin server failed.

When You See It

When origin SSL certificate is expired, misconfigured, or incompatible.

How to Fix

Check origin SSL certificate validity. Ensure TLS version compatibility. Renew expired certificates.

Key Differences

1.

425 is a 4xx Client Error response, while 525 is a 5xx Server Error response.

2.

HTTP 425: The server is unwilling to risk processing a request that might be replayed. Used with TLS 1.3 early data (0-RTT).

3.

HTTP 525: Cloudflare-specific. SSL/TLS handshake with the origin server failed.

4.

You encounter 425 when when a server rejects a request sent as TLS 1.3 early data due to replay risk.

5.

You encounter 525 when when origin SSL certificate is expired, misconfigured, or incompatible.

When to Use Which

For 425 (Too Early): Retry the request after the TLS handshake completes. For 525 (SSL Handshake Failed): Check origin SSL certificate validity. Ensure TLS version compatibility. Renew expired certificates.

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