BugZero | F5 BugID 1024761 - HTTP adds Transfer-Encoding and terminating chunk ...

F5 - Defect ID: 1024761

HTTP adds Transfer-Encoding and terminating chunk to responses that cannot have a body

F5 - Defect ID: 1024761

HTTP adds Transfer-Encoding and terminating chunk to responses that cannot have a body

Last updated on December 31st, 2025

BugZero Risk Score
5.9 Medium

Overall: 5.9

Severity: 6.4

Community: 4.2

Lifecycle: 7.0

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Bug Details

Priority: 4-Minor
Status: Verified
Impact Category: Local Traffic Manager
Views: 3

Description

Symptoms

When rechunking is requested, HTTP responses with methods or status codes indicating that no body be present (like HEAD or 304) are receiving a Transfer-Encoding header and a terminating chunk. These responses should not have a body of any sort.

Impact

HTTP clients are unable to connect.

Conditions

HTTP virtual server with rewrite profile present with the server that does HTTP caching.

Workaround

Remove the rewrite profile. Possibly change http profile response-chunking from sustain to unchunk. This resolves the issue for the 304, but means that all other requests are changed from either chunking or unchunked with Content-Length header to unchunked without Content-Length and with "Connection: Close".

Fix Information

None

Change history

2025-04-28 Added: 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, 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

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, 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

Fixed versions: 17.0.0, 16.1.2.1, 15.1.5

Relevant Products

Click on a version to see all relevant bugs

Fixed versions: 17.0.0, 16.1.2.1, 15.1.5

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F5 - Defect ID: 1024761

HTTP adds Transfer-Encoding and terminating chunk to responses that cannot have a body

F5 - Defect ID: 1024761

HTTP adds Transfer-Encoding and terminating chunk to responses that cannot have a body

Last updated on December 31st, 2025

BugZero Risk Score5.9 Medium

Bug Details

Symptoms

Impact

Conditions

Workaround

Fix Information

Links

Top F5 Defects

Ready to prevent the next vendor outage?

BugZero Risk Score
5.9 Medium