> Source: [sk173266](https://support.checkpoint.com/results/sk/sk173266)

# sk173266 - Remote Access users are unable to exchange traffic with Security Gateway due to Anti Spoofing drops

| Property | Value |
|----------|-------|
| Solution ID | sk173266 |
| Date Created | 2021-04-27 |
| Last Modified | 2021-07-11 |
| Technical Level | General |
| Products | Security Gateway |
| Versions | R81 (EOS) |

## Symptoms

- * Remote Access users are unable to reach the encryption domain.
* Anti Spoofing drops on the Office Mode IP observed in SecureXL debugs.

## Cause

* SecureXL uses the wrong Anti Spoofing handling for accelerated connections in VSX environments.
* This issue can happen in environments where there is an overlap between the Office Mode and the internal networks.

## Solution

This problem was fixed. The fix is included in:

* [Jumbo Hotfix Accumulator for R81](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk170114) starting from Take 34
* [Jumbo Hotfix Accumulator for R80.40](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk165456) starting from Take 119
* [Jumbo Hotfix Accumulator for R80.30](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk153152) starting from Take 237
* [Jumbo Hotfix Accumulator for R80.20](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk137592) starting from Take 202

If you choose not to upgrade, Check Point can supply a **Hotfix** . [Contact Check Point Support](https://www.checkpoint.com/support-services/contact-support/) to get a Hotfix for this issue.  
A Support Engineer will make sure the Hotfix is compatible with your environment before providing the Hotfix.  
For faster resolution and verification, please collect [CPinfo files](http://supportcontent.checkpoint.com/solutions?id=sk92739) from the Security Management Server and Security Gateways involved in the case.

**Hotfix installation instructions:**   
Refer to [sk168597 - How to install a Hotfix](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk168597).

<br />

For a quick work-around, on the External network interface set the **Anti-Spoofing** to**Detect** .

1. Open SmartConsole.

2. In the left pane, select **Network Management**.

3. In the center pane, select the relevant External network.

   A new window opens.
4. Under **Topology** , click **Modify...**

   A new window opens.
5. Under Anti-Spoofing, make sure that **perform Anti-Spoofing based on interface topology** is selected.

6. To the right of **Anti-Spoofing action is set to** , select **Detect**.

7. Click **OK**.

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