> Source: [sk182725](https://support.checkpoint.com/results/sk/sk182725)

# sk182725 - Anti-Spoofing drops IPv6 traffic that arrives at an interface with an IPv6 address configured

| Property | Value |
|----------|-------|
| Solution ID | sk182725 |
| Date Created | 2024-10-01 |
| Last Modified | 2025-01-27 |
| Technical Level | General |
| Products | Security Gateway |
| Versions | R82, R81.20, R81.10 (EOS) |
| OS | Gaia |
| Platform | Open Server |

## Symptoms

- Anti-Spoofing drops IPv6 traffic that arrives at an interface with an IPv6 address configured. The logs show:
`@;272246227;[kern];[tid_37];[SIM-241695243];sim_pkt_send_drop_notification: sending single drop notification, conn: <2001:b68:ff:12:4605:4035:f5a0:1867,6,fdca:0:0:2:0:0:32:2,128,58>;`  
`@;272246227;[kern];[tid_37];[SIM-241695243];do_packet_finish: SIMPKT_IN_DROP vsid=2, conn:<2001:b68:ff:12:4605:4035:f5a0:1867,6,fdca:0:0:2:0:0:32:2,128,58>;`  
`@;37145111;[vs_2];[tid_0];[fw6_0];cphwd_notif_packet_dropped: `**received packet dropped notification, reason: Anti-Spoofing****;**  
`@;37145111;[vs_2];[tid_0];[fw6_0];cphwd_notif_packet_dropped: notification holds a single drop;`

## Cause

The IPv6 addresses were miscalculated when exceptions were added from the external interface.

<br />

## Solution

This problem was fixed. The fix is included in:

* [Jumbo Hotfix Accumulator for R82](https://sc1.checkpoint.com/documents/Jumbo_HFA/R82/Default.htm) starting from Take 10
* [Jumbo Hotfix Accumulator for R81.20](https://sc1.checkpoint.com/documents/Jumbo_HFA/R81.20/Default.htm) starting from Take 90
* [Jumbo Hotfix Accumulator for R81.10](https://sc1.checkpoint.com/documents/Jumbo_HFA/R81.10/Default.htm) starting from Take 171

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).

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