BugZero | F5 BugID 985749 - TCP exponential backoff algorithm does not comply ...

F5 - Defect ID: 985749

TCP exponential backoff algorithm does not comply with RFC 6298

F5 - Defect ID: 985749

TCP exponential backoff algorithm does not comply with RFC 6298

Last updated on July 28th, 2026

BugZero Risk Score
7.0 High

Overall: 7.0

Severity: 7.3

Community: 4.2

Lifecycle: 10.0

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Bug Details

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

Description

Symptoms

The algorithms used for TCP exponential backoff are different for SYN and non-SYN packets.

Impact

Retransmission timeout interval depends on the inclusion/exclusion of SYN flag.

Conditions

Using TCP.

Workaround

None

Fix Information

None

Change history

Links

Original Vendor Announcement

Relevant Products

Click on a version to see all relevant bugs

Affected versions:11.6.5, 11.6.5.1, 11.6.5.2, 11.6.5.3, 12.1.6, 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, 14.1.0, 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, 15.1.2, 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, 16.1.3.4, 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, 17.5.0, 17.5.1, 17.5.1.2, 17.5.1.3, 17.5.1.4, 17.5.1.5, 17.5.1.6, 17.5.1.8, 21.0.0, 21.0.0.1, 21.0.0.2, 21.0.0.3

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: 985749

TCP exponential backoff algorithm does not comply with RFC 6298

F5 - Defect ID: 985749

TCP exponential backoff algorithm does not comply with RFC 6298

Last updated on July 28th, 2026

BugZero Risk Score7.0 High

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

F5 - Defect ID: 985749

TCP exponential backoff algorithm does not comply with RFC 6298

F5 - Defect ID: 985749

TCP exponential backoff algorithm does not comply with RFC 6298

Last updated on July 28th, 2026

BugZero Risk Score7.0 High

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

BugZero Risk Score
7.0 High

BugZero Risk Score
7.0 High