> Source: [sk109555](https://support.checkpoint.com/results/sk/sk109555)

# sk109555 - HTTPS traffic dropped by IPS protection "Non Compliant HTTP"

| Property | Value |
|----------|-------|
| Solution ID | sk109555 |
| Date Created | 2016-01-13 |
| Last Modified | 2017-12-18 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- * HTTPS websites are blocked by the IPS protection: Non Compliant HTTP
* Drop log in SmartView Tracker for port 443: `"illegal header format detected: Malformed HTTP format in request"`

## Cause

Traffic was matched on a custom https service with http header.

IPS engine is designed to enforce its protection according to RFC. Due to that fact, IPS identified HTTP handler under the custom service and continued to perform further checks under IPS.

This protection should not run on SSL handshake traffic.

## Solution

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

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