BugZero | F5 BugID 766593 - RESOLV::lookup with bytes array input does not wor...

F5 - Defect ID: 766593

RESOLV::lookup with bytes array input does not work when length is exactly 4, 16, or 20

F5 - Defect ID: 766593

RESOLV::lookup with bytes array input does not work when length is exactly 4, 16, or 20

Last updated on July 18th, 2026

BugZero Risk Score
6.9 Medium

Overall: 6.9

Severity: 7.3

Community: 4.2

Lifecycle: 8.7

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Bug Details

Priority: 3-Major
Status: Resolved
Impact Category: Global Traffic Manager (DNS)

Description

Symptoms

RESOLV::lookup returns empty string.

Impact

RESOLV::lookup returns empty string.

Conditions

Input bytes array is at length of 4, 16, or 20. For example: [RESOLV::lookup @dnsserveraddress -a [binary format a* $host1.d1test.com]]

Workaround

Use lindex 0 to get the first element of the array. For example: [RESOLV::lookup @dnsserveraddress -a [lindex [binary format a* $host1.d1test.com] 0]]

Fix Information

None

Change history

Links

Original Vendor Announcement

Relevant Products

Click on a version to see all relevant bugs

Affected versions: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, 12.1.5, 12.1.5.1, 12.1.5.2, 12.1.5.3, 12.1.6, 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, 13.1.3, 13.1.3.1, 13.1.3.2, 13.1.3.3, 13.1.3.4, 13.1.3.5, 13.1.3.6, 13.1.4, 13.1.4.1, 13.1.5, 13.1.5.1, 14.0.0, 14.0.0.1, 14.0.0.2, 14.0.0.3, 14.0.0.4, 14.0.0.5, 14.0.1, 14.0.1.1, 14.1.0, 14.1.0.1, 14.1.0.2, 14.1.0.3, 14.1.0.5, 14.1.0.6, 14.1.2, 14.1.2.1, 14.1.2.2, 14.1.2.3, 14.1.2.4, 14.1.2.5, 14.1.2.6, 14.1.2.7, 14.1.2.8, 14.1.3, 14.1.3.1, 14.1.4, 14.1.4.1, 14.1.4.2, 14.1.4.3, 14.1.4.4, 14.1.4.5, 14.1.4.6, 14.1.5, 14.1.5.1, 14.1.5.2, 14.1.5.3, 14.1.5.4, 14.1.5.6, 15.0.0, 15.0.1, 15.0.1.1, 15.0.1.2, 15.0.1.3, 15.0.1.4, 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

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: 766593

RESOLV::lookup with bytes array input does not work when length is exactly 4, 16, or 20

F5 - Defect ID: 766593

RESOLV::lookup with bytes array input does not work when length is exactly 4, 16, or 20

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: 766593

RESOLV::lookup with bytes array input does not work when length is exactly 4, 16, or 20

F5 - Defect ID: 766593

RESOLV::lookup with bytes array input does not work when length is exactly 4, 16, or 20

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