> Source: [sk184704](https://support.checkpoint.com/results/sk/sk184704)

# sk184704 - HTTP 400 Bad Request error caused by large cookies or request headers

| Property | Value |
|----------|-------|
| Solution ID | sk184704 |
| Date Created | 2026-03-08 |
| Last Modified | 2026-03-10 |
| Technical Level | Advanced |
| Products | WAF Application Security |
| Versions | Cloud |

## Symptoms

- * The browser shows **400 Bad Request** error.
* NGINX error logs show messages such as:
  * `client intended to send too large header`
  * `request header or cookie too large (400 Bad Request)`
* Clearing cookies can temporarily fix the issue.

## Cause

The issue occurs when the total size of incoming HTTP request headers exceeds the buffer limits configured in NGINX.  
This is most commonly caused by:

* Large authentication tokens (for example, JWTs)
* Large session cookies
* Accumulated application or tracking cookies over time

## Solution

This solution requires authentication. Please log in to view the full solution.

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