BugZero | F5 BugID 503541 - Use 64 bit instead of 10 bit for Rate Tracker libr...

F5 - Defect ID: 503541

Use 64 bit instead of 10 bit for Rate Tracker library hashing.

F5 - Defect ID: 503541

Use 64 bit instead of 10 bit for Rate Tracker library hashing.

Last updated on July 18th, 2026

BugZero Risk Score
8.7 High

Overall: 8.7

Severity: 9.1

Community: 4.2

Lifecycle: 10.0

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Bug Details

Priority: 2-Critical
Status: Resolved
Impact Category: Advanced Firewall Manager

Description

Symptoms

Rate Tracker 10 bit hashing may cause inaccurate rate-limits by the Sweep & Flood DoS vectors.

Impact

Impact to Sweep and Flood detection rate accuracy.

Conditions

When Sweep and Flood vector is enabled in AFM module.

Workaround

None.

Fix Information

The system now uses 64 bit instead of 10 bit for Rate Tracker hashing, which results in more accuracy in attack detection and mitigation.

Change history

Links

Original Vendor Announcement

Relevant Products

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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

Fixed versions: 12.0.0

Relevant Products

Click on a version to see all relevant bugs

Fixed versions: 12.0.0

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F5 - Defect ID: 503541

Use 64 bit instead of 10 bit for Rate Tracker library hashing.

F5 - Defect ID: 503541

Use 64 bit instead of 10 bit for Rate Tracker library hashing.

Last updated on July 18th, 2026

BugZero Risk Score8.7 High

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

F5 - Defect ID: 503541

Use 64 bit instead of 10 bit for Rate Tracker library hashing.

F5 - Defect ID: 503541

Use 64 bit instead of 10 bit for Rate Tracker library hashing.

Last updated on July 18th, 2026

BugZero Risk Score8.7 High

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

BugZero Risk Score
8.7 High

BugZero Risk Score
8.7 High