BugZero | F5 BugID 1599921 - SSL memory growth on standby.

F5 - Defect ID: 1599921

SSL memory growth on standby.

F5 - Defect ID: 1599921

SSL memory growth on standby.

Last updated on July 28th, 2026

BugZero Risk Score
6.7 Medium

Overall: 6.7

Severity: 7.3

Community: 4.2

Lifecycle: 6.4

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Bug Details

Priority: 3-Major
Status: New
Impact Category: Local Traffic Manager

Description

Symptoms

SSL memory use spikes more than it should when SSL traffic increases and then falls back down as connections are closed.

Impact

Memory pressure on standby box sometimes causing the aggressive mode sweeper to activate.

Conditions

No repro as yet so conditions are not completely clear but need: * SSL traffic * HA pair with mirroring enabled.

Workaround

Disable mirroring on virtual servers.

Fix Information

None

Change history

Links

Original Vendor Announcement

Relevant Products

Click on a version to see all relevant bugs

Affected versions:15.1.0, 15.1.0.1, 15.1.0.2, 15.1.0.3, 15.1.0.4, 15.1.0.5, 15.1.1, 15.1.2, 15.1.2.1, 15.1.3, 15.1.3.1, 15.1.4, 15.1.4.1, 15.1.5, 15.1.5.1, 15.1.6, 15.1.6.1, 15.1.7, 15.1.8, 15.1.8.1, 15.1.8.2, 15.1.9, 15.1.9.1, 15.1.10, 15.1.10.2, 15.1.10.3, 15.1.10.4, 15.1.10.5, 15.1.10.6, 15.1.10.7, 15.1.10.8, 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, 16.1.5, 16.1.5.1, 16.1.5.2, 16.1.6, 16.1.6.1, 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, 17.1.2, 17.1.2.1, 17.1.2.2, 17.1.3, 17.1.3.1, 17.1.3.2, 17.1.3.4

Fixed versions: No known fixed versions

Relevant Products

Click on a version to see all relevant bugs

Fixed versions: No known fixed versions

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F5 - Defect ID: 1599921

SSL memory growth on standby.

F5 - Defect ID: 1599921

SSL memory growth on standby.

Last updated on July 28th, 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: 1599921

SSL memory growth on standby.

F5 - Defect ID: 1599921

SSL memory growth on standby.

Last updated on July 28th, 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