BugZero | F5 BugID 1388985 - The daemon dwbld uses 100% CPU when max port value...

F5 - Defect ID: 1388985

The daemon dwbld uses 100% CPU when max port value configured in TMC port list

F5 - Defect ID: 1388985

The daemon dwbld uses 100% CPU when max port value configured in TMC port list

Last updated on July 18th, 2026

BugZero Risk Score
6.7 Medium

Overall: 6.7

Severity: 7.3

Community: 4.2

Lifecycle: 7.0

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Bug Details

Priority: 3-Major
Status: Verified
Impact Category: Advanced Firewall Manager

Description

Symptoms

When Traffic Matching Criteria (TMC) port list range is configured that includes maximum port value of 65535, counter is incremented till 65535 and wraps back to 0, as the variable used to store the counter is uint16_t.

Impact

The daemon dwbld consumes 100% CPU impacting system performance.

Conditions

- AFM license enabled. - Daemon dwbld enabled - Any TMC port list configured with maximum port value of 65535

Workaround

Avoid configuring maximum port value of 65535 in TMC port list range.

Fix Information

The counter is changed to uint32_t to avoid rollover when maximum port value is included in port list range.

Change history

Links

Original Vendor Announcement

Relevant Products

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Affected versions:16.0.0, 16.0.0.1, 16.0.1, 16.0.1.1, 16.0.1.2, 16.1.0, 16.1.1, 16.1.2, 16.1.2.1, 16.1.2.2, 16.1.3, 16.1.3.1, 16.1.3.2, 16.1.3.3, 16.1.3.4, 16.1.3.5, 16.1.4, 16.1.4.1, 16.1.4.2, 16.1.4.3, 17.0.0, 17.0.0.1, 17.0.0.2, 17.1.0, 17.1.0.1, 17.1.0.2, 17.1.0.3, 17.1.1, 17.1.1.1, 17.1.1.2, 17.1.1.3, 17.1.1.4

Fixed versions: 17.5.0, 17.1.2, 16.1.5

Relevant Products

Click on a version to see all relevant bugs

Fixed versions: 17.5.0, 17.1.2, 16.1.5

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F5 - Defect ID: 1388985

The daemon dwbld uses 100% CPU when max port value configured in TMC port list

F5 - Defect ID: 1388985

The daemon dwbld uses 100% CPU when max port value configured in TMC port list

Last updated on July 18th, 2026

BugZero Risk Score6.7 Medium

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

F5 - Defect ID: 1388985

The daemon dwbld uses 100% CPU when max port value configured in TMC port list

F5 - Defect ID: 1388985

The daemon dwbld uses 100% CPU when max port value configured in TMC port list

Last updated on July 18th, 2026

BugZero Risk Score6.7 Medium

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

BugZero Risk Score
6.7 Medium

BugZero Risk Score
6.7 Medium