> Source: [sk21181](https://support.checkpoint.com/results/sk/sk21181)

# sk21181 - "Address spoofing" drop log 

| Property | Value |
|----------|-------|
| Solution ID | sk21181 |
| Date Created | 2003-07-15 |
| Last Modified | 2022-11-27 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R81.20, R81.10 (EOS), R81 (EOS) |

## Symptoms

- Logs show that traffic is dropped with "`message_info: Address spoofing`" in the "`Information`" field.  
These logs appear for inbound packets on the external interface of Security Gateway, although these packets were received from the network that belongs to the same external interface.

## Cause

Anti-Spoofing misconfiguration on the external interface of the Security Gateway.

## Solution

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

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