> Source: [sk66273](https://support.checkpoint.com/results/sk/sk66273)

# sk66273 - Meaning of "dropped by fw_early_sip_nat Reason: spoofed packet"

| Property | Value |
|----------|-------|
| Solution ID | sk66273 |
| Date Created | 2012-02-05 |
| Last Modified | 2019-08-07 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |

## Symptoms

- SIP (UDP 5060) traffic is dropped with error message: "fw_early_sip_nat Reason: spoofed packet"

## Cause

Anti-spoofing mis-configured.

## Solution

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