BugZero | F5 BugID 566361 - RAM Cache Key Collision

F5 - Defect ID: 566361

RAM Cache Key Collision

F5 - Defect ID: 566361

RAM Cache Key Collision

Last updated on July 18th, 2026

BugZero Risk Score
6.9 Medium

Overall: 6.9

Severity: 7.3

Community: 4.2

Lifecycle: 8.3

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Bug Details

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

Description

Symptoms

Intermittent tmm SIGSEGV when RAM Cache is enabled

Impact

Invalid response format, and/or serving the wrong object from cache, and/or tmm crash, interruption of service.

Conditions

This occurs when RAM cache is enabled in certain circumstances.

Workaround

None.

Fix Information

The system now avoids RAM Cache Key collisions, the correct object and response format are delivered from the cache, and tmm no longer cores.

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, 11.6.5.2, 11.6.5.3, 12.0.0, 12.0.0 hf1, 12.0.0 hf2, 12.0.0 hf3, 12.0.0 hf4

Fixed versions: 12.1.0

Relevant Products

Click on a version to see all relevant bugs

Fixed versions: 12.1.0

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F5 - Defect ID: 566361

RAM Cache Key Collision

F5 - Defect ID: 566361

RAM Cache Key Collision

Last updated on July 18th, 2026

BugZero Risk Score6.9 Medium

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

F5 - Defect ID: 566361

RAM Cache Key Collision

F5 - Defect ID: 566361

RAM Cache Key Collision

Last updated on July 18th, 2026

BugZero Risk Score6.9 Medium

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

BugZero Risk Score
6.9 Medium

BugZero Risk Score
6.9 Medium