BugZero | F5 BugID 555464 - HA channel flapping will cause SessionDB memory le...

F5 - Defect ID: 555464

HA channel flapping will cause SessionDB memory leak on standby due to unexpired entries

F5 - Defect ID: 555464

HA channel flapping will cause SessionDB memory leak on standby due to unexpired entries

Last updated on July 18th, 2026

BugZero Risk Score
8.4 High

Overall: 8.4

Severity: 9.1

Community: 4.2

Lifecycle: 7.0

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Bug Details

Priority: 2-Critical
Status: Verified
Impact Category: TMOS

Description

Symptoms

SessionDB memory leak on a standby in the HA pair due to HA channel flapping causing failure of expiry messages.

Impact

Slow memory leakage on the standby

Conditions

SessionDB in use, HA channel errors

Workaround

Alleviate the HA flapping and then restart the standby.

Fix Information

None

Change history

Links

Original Vendor Announcement

Relevant Products

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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, 11.6.0, 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

Fixed versions: 12.1.0, 11.6.5.2, 11.5.9

Relevant Products

Click on a version to see all relevant bugs

Fixed versions: 12.1.0, 11.6.5.2, 11.5.9

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F5 - Defect ID: 555464

HA channel flapping will cause SessionDB memory leak on standby due to unexpired entries

F5 - Defect ID: 555464

HA channel flapping will cause SessionDB memory leak on standby due to unexpired entries

Last updated on July 18th, 2026

BugZero Risk Score8.4 High

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

F5 - Defect ID: 555464

HA channel flapping will cause SessionDB memory leak on standby due to unexpired entries

F5 - Defect ID: 555464

HA channel flapping will cause SessionDB memory leak on standby due to unexpired entries

Last updated on July 18th, 2026

BugZero Risk Score8.4 High

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

BugZero Risk Score
8.4 High

BugZero Risk Score
8.4 High