Bug ID 781753: WebSocket traffic is transmitted with unknown opcodes

Last Modified: Sep 13, 2023

Affected Product(s):
BIG-IP LTM(all modules)

Known Affected Versions:
13.1.1,,,,, 13.1.3,

Fixed In:

Opened: May 13, 2019

Severity: 3-Major


The BIG-IP system does not preserve WebSocket frames. Frame headers and payload may be reordered such that a header for a second frame may be sent out in the middle of a first frame's payload. Frame boundaries get skewed and payload gets interpreted as headers.


WebSocket frames are not preserved such that traffic appears to be garbage. -- If request logging is enabled, client frames may not be preserved. -- If response logging is enabled, server frames may not be preserved.


A request logging profile is configured on a WebSocket virtual server.


Remove the request logging profile.

Fix Information


Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips