BugZero | F5 BugID 514635 - TMM Cores with D-SACK

F5 - Defect ID: 514635

TMM Cores with D-SACK

F5 - Defect ID: 514635

TMM Cores with D-SACK

Last updated on July 18th, 2026

BugZero Risk Score
8.3 High

Overall: 8.3

Severity: 9.1

Community: 4.2

Lifecycle: 5.8

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Bug Details

Priority: 2-Critical
Status: Closed
Impact Category: Local Traffic Manager

Description

Symptoms

When TCP SACK and D-SACK are enabled, TMM may crash.

Impact

Traffic disrupted while tmm restarts.

Conditions

TCP SACK and D-SACK enabled.

Workaround

Disable D-SACK.

Fix Information

None

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, 11.6.0, 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

Fixed versions: 12.0.0, 11.5.2

Relevant Products

Click on a version to see all relevant bugs

Fixed versions: 12.0.0, 11.5.2

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F5 - Defect ID: 514635

TMM Cores with D-SACK

F5 - Defect ID: 514635

TMM Cores with D-SACK

Last updated on July 18th, 2026

BugZero Risk Score8.3 High

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

F5 - Defect ID: 514635

TMM Cores with D-SACK

F5 - Defect ID: 514635

TMM Cores with D-SACK

Last updated on July 18th, 2026

BugZero Risk Score8.3 High

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

BugZero Risk Score
8.3 High

BugZero Risk Score
8.3 High