Bug ID 680264: HTTP2 headers frame decoding may fail when the frame delivered in multiple xfrags

Last Modified: Jun 30, 2021

Bug Tracker

Affected Product:  See more info
BIG-IP LTM(all modules)

Known 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,,,,,,,, 13.0.0, 13.0.0 HF1, 13.0.0 HF2, 13.0.0 HF3, 13.1.0,,,

Fixed In:
14.0.0,, 13.0.1, 12.1.4

Opened: Aug 26, 2017
Severity: 3-Major
Related AskF5 Article:


Intermittently, HTTP2 experiences protocol resets.


Unexpected loss of HTTP2 frames due to protocol resets.


-- xfrag is 2 bytes in length. -- The header length is greater than 128. -- xfrag starts. For example, the following returns the incorrect header length: (0xFF BYTE1) next byte, http2_arbint_read.


No effective workaround.

Fix Information

HTTP2 now parses the request, regardless of its xfrags distribution.

Behavior Change