BugZero | F5 BugID 514604 - Nexthop object can be freed while still referenced...

F5 - Defect ID: 514604

Nexthop object can be freed while still referenced by another structure

F5 - Defect ID: 514604

Nexthop object can be freed while still referenced by another structure

Last updated on July 18th, 2026

BugZero Risk Score
6.8 Medium

Overall: 6.8

Severity: 7.3

Community: 4.2

Lifecycle: 7.8

What is the BugZero Risk Score?

F5 Integration

Learn more about where this data comes from

F5 Integration

Learn more

BugZero Plan

Streamline upgrades with automated vendor bug scrubs

BugZero Plan

Learn more

BugZero Prevent

Wish you caught this bug sooner? Get proactive today.

BugZero Prevent

Learn more

Bug Details

Priority: 3-Major
Status: Not Verified
Impact Category: Local Traffic Manager

Description

Symptoms

Use after free of the Nexthop object may cause memory corruption or tmm core.

Impact

The BIG-IP system might crash. This is a very timing/memory-usage dependent issue that is rarely encountered.

Conditions

This can happen if the proxy connection takes some time to complete, creating a large enough time window where the nexthop object might be freed.

Workaround

None.

Fix Information

Management of nexthop object reference counting is more consistent.

Change history

Links

Original Vendor Announcement

Relevant Products

Click on a version to see all relevant bugs

Affected versions:11.5.1, 11.5.1 hf1, 11.5.1 hf2, 11.5.1 hf3, 11.5.1 hf4, 11.5.1 hf5, 11.5.1 hf6, 11.5.1 hf7, 11.5.1 hf8, 11.5.1 hf9, 11.5.1 hf10, 11.5.1 hf11, 11.5.2, 11.5.2 hf1, 11.5.3, 11.5.3 hf1, 11.5.3 hf2, 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

Fixed versions: 12.0.0, 11.6.2

Relevant Products

Click on a version to see all relevant bugs

Fixed versions: 12.0.0, 11.6.2

Top F5 Defects

9.6Defect ID: 546260
TMM can crash if using the v6rd profile
9.6Defect ID: 934133
Unable to Create/delete ltm virtual server via CLI transaction when destination is not specified on the ltm virtual object
9.6Defect ID: 1154417
Profile based attack is not mitigated at hardware on L2 wire setup
9.6Defect ID: 913713
Rebooting a blade causes MCPd to core as it rejoins the cluster
9.6Defect ID: 2141125
Multicast traffic is dropped with incorrect VLAN tagging

F5 Integration

Learn more about where this data comes from

F5 Integration

Learn more

BugZero Plan

Streamline upgrades with automated vendor bug scrubs

BugZero Plan

Learn more

BugZero Prevent

Wish you caught this bug sooner? Get proactive today.

BugZero Prevent

Learn more

Ready to prevent the next vendor outage?

Get a demo

F5 - Defect ID: 514604

Nexthop object can be freed while still referenced by another structure

F5 - Defect ID: 514604

Nexthop object can be freed while still referenced by another structure

Last updated on July 18th, 2026

BugZero Risk Score6.8 Medium

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

F5 - Defect ID: 514604

Nexthop object can be freed while still referenced by another structure

F5 - Defect ID: 514604

Nexthop object can be freed while still referenced by another structure

Last updated on July 18th, 2026

BugZero Risk Score6.8 Medium

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

BugZero Risk Score
6.8 Medium

BugZero Risk Score
6.8 Medium