> Source: [sk165715](https://support.checkpoint.com/results/sk/sk165715)

# sk165715 - Security Gateway drops traffic for "TCP Invalid Combination"

| Property | Value |
|----------|-------|
| Solution ID | sk165715 |
| Date Created | 2020-03-11 |
| Last Modified | 2020-03-16 |
| Technical Level | Advanced |
| Products | Security Gateway |
| Versions | R82.10, R82, R81.20 |
| OS | Gaia |

## Symptoms

- * Security Gateway drops traffic for "TCP Invalid Combination".
* Implementation of [sk43750](https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solutionid=sk43750) does not solve the issue.
* In the traffic capture, see the following combination:  
  \[FIN , PSH, URG\]   
  [![](https://sc1.checkpoint.com/sc/SolutionsStatics/NEW_SK_NOID1583910063619/Capturewith IPs20200311095223.gif)](https://sc1.checkpoint.com/sc/SolutionsStatics/NEW_SK_NOID1583910063619/Capturewith IPs20200311095223.gif "Click the image to see it in full size in a new tab/window")

## Solution

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

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