Bug ID 640369: TMM may incorrectly respond to ICMPv6 echo via auto-lasthop when disabled on the vlan

Last Modified: Aug 19, 2026

Affected Product(s):
BIG-IP LTM(all modules)

Known Affected Versions:
11.5.4, 11.5.4 hf1, 11.5.4 hf2, 11.5.4 hf3, 11.5.4 hf4, 11.5.5, 11.5.6, 11.5.7, 11.5.8, 11.5.9, 11.5.10, 11.6.0, 11.6.0 hf1, 11.6.0 hf2, 11.6.0 hf3, 11.6.0 hf4, 11.6.0 hf5, 11.6.0 hf6, 11.6.0 hf7, 11.6.0 hf8, 11.6.1, 11.6.1 hf1, 11.6.1 hf2, 11.6.2, 11.6.2 hf1, 11.6.3, 11.6.3.1, 11.6.3.2, 11.6.3.3, 11.6.3.4, 11.6.4, 11.6.5, 11.6.5.1, 11.6.5.2, 11.6.5.3, 12.0.0, 12.0.0 hf1, 12.0.0 hf2, 12.0.0 hf3, 12.0.0 hf4, 12.1.0, 12.1.0 hf1, 12.1.0 hf2, 12.1.1, 12.1.1 hf1, 12.1.1 hf2, 12.1.2, 12.1.2 hf1, 12.1.2 hf2, 12.1.3, 12.1.3.1, 12.1.3.2, 12.1.3.3, 13.0.0, 13.0.0 hf1, 13.0.0 hf2, 13.0.0 hf3, 13.0.1

Fixed In:
13.1.0, 12.1.3.4

Opened: Jan 19, 2017

Severity: 3-Major

Symptoms

As a result of a known issue, TMM may respond to an ICMPv6 echo request using the auto-lasthop mechanism, when this has been disabled on the vlan.

Impact

Traffic may not follow the expected path.

Conditions

- Auto-lasthop disabled on the ingress vlan - ICMPv6 echo request for a self-IP on the ingress vlan. - Route to the client IP address via a different vlan TMM may respond directly using the auto-lasthop feature and not via the route lookup.

Workaround

None

Fix Information

TMM now correctly uses the configured option for auto-lashop and ICMPv6 traffic

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips