Bug ID 744949: MRF SIP ALG with SNAT may restore incorrect client identity if client IP does not match NAT64 prefix

Last Modified: Nov 07, 2022

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

Known Affected Versions:
13.1.0,,,,,,,,, 13.1.1,,,, 14.0.0,,,,,, 14.0.1, 14.1.0,

Fixed In:

Opened: Sep 24, 2018

Severity: 3-Major


SIP response messages have the wrong IP address in the FROM header when using NAT64.


The SIP ALG with SNAT system will be unable to establish a call for the client.


If the client's IPv6 address does not match the virtual server's configured IPv6 prefix, the FROM header on a response message will have a different IP address that the request message.


There is no workaround at this time.

Fix Information

The FROM header will now contain the client's IP address.

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips