BugZero | F5 BugID 667779 - iRule commands may cause the TMM to crash in very ...

F5 - Defect ID: 667779

iRule commands may cause the TMM to crash in very rare situations.

F5 - Defect ID: 667779

iRule commands may cause the TMM to crash in very rare situations.

Last updated on July 18th, 2026

BugZero Risk Score
8.6 High

Overall: 8.6

Severity: 9.1

Community: 4.2

Lifecycle: 8.3

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Bug Details

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

Description

Symptoms

A TMM crash may occur in very rare situations.

Impact

A TMM Core. Traffic disrupted while tmm restarts.

Conditions

A Tcl iRule command is used.

Workaround

None.

Fix Information

Tcl iRule commands are more robust to extreme scenarios within the TMM.

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, 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, 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, 12.1.3.4, 12.1.3.5, 12.1.3.6, 12.1.3.7, 12.1.4, 12.1.4.1, 13.0.0, 13.0.0 hf1, 13.0.0 hf2, 13.0.0 hf3, 13.0.1, 13.1.0, 13.1.0.1, 13.1.0.2, 13.1.0.3, 13.1.0.4, 13.1.0.5, 13.1.0.6, 13.1.0.7, 13.1.0.8, 13.1.1, 13.1.1.2, 13.1.1.3, 13.1.1.4, 13.1.1.5

Fixed versions: 14.0.0, 13.1.3, 12.1.5, 11.6.5.2

Relevant Products

Click on a version to see all relevant bugs

Fixed versions: 14.0.0, 13.1.3, 12.1.5, 11.6.5.2

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F5 Integration

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F5 - Defect ID: 667779

iRule commands may cause the TMM to crash in very rare situations.

F5 - Defect ID: 667779

iRule commands may cause the TMM to crash in very rare situations.

Last updated on July 18th, 2026

BugZero Risk Score8.6 High

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

F5 - Defect ID: 667779

iRule commands may cause the TMM to crash in very rare situations.

F5 - Defect ID: 667779

iRule commands may cause the TMM to crash in very rare situations.

Last updated on July 18th, 2026

BugZero Risk Score8.6 High

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

BugZero Risk Score
8.6 High

BugZero Risk Score
8.6 High