> Source: [sk110758](https://support.checkpoint.com/results/sk/sk110758)

# sk110758 - When MTA enabled, port 25 is open on all gateway interfaces by default

| Property | Value |
|----------|-------|
| Solution ID | sk110758 |
| Date Created | 2016-04-19 |
| Last Modified | 2018-11-05 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |

## Symptoms

- When MTA is enabled Port 25 is open on all gateway interfaces for connections destined to the gateway.

## Cause

When MTA is enabled, it creates an Implied Rule which opens port 25 on all gateway interfaces for connections destined to the gateway by default.

## Solution

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

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