Last Modified: Jul 18, 2026
Affected Product(s):
BIG-IP LTM
Known Affected Versions:
11.5.1, 11.5.1 hf1, 11.5.1 hf2, 11.5.1 hf3, 11.5.1 hf4, 11.5.1 hf5, 11.5.1 hf6, 11.5.1 hf7, 11.5.1 hf8, 11.5.1 hf9, 11.5.1 hf10, 11.5.1 hf11, 11.5.2, 11.5.2 hf1, 11.5.3, 11.5.3 hf1, 11.5.3 hf2, 11.5.4, 11.5.4 hf1, 11.5.4 hf2, 11.5.4 hf3, 11.5.4 hf4, 11.5.5, 11.6.0, 11.6.0 hf1, 11.6.0 hf2, 11.6.0 hf3, 11.6.0 hf4, 11.6.0 hf5, 11.6.0 hf6, 11.6.0 hf7, 11.6.0 hf8, 11.6.1, 11.6.1 hf1, 11.6.1 hf2, 11.6.2, 11.6.2 hf1, 11.6.3, 11.6.3.1, 11.6.3.2, 12.0.0, 12.0.0 hf1, 12.0.0 hf2, 12.0.0 hf3, 12.0.0 hf4, 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, 12.1.3.1, 12.1.3.2, 12.1.3.3, 12.1.3.4, 12.1.3.5, 12.1.3.6, 13.0.0, 13.0.0 hf1, 13.0.0 hf2, 13.0.0 hf3, 13.0.1
Fixed In:
13.1.0, 12.1.3.7, 11.6.3.3, 11.5.6
Opened: Feb 05, 2016 Severity: 3-Major
When using a pool route, it is possible for TCP connections to emit packets onto the network that have a source MAC address of 00:98:76:54:32:10. This is the MAC address of Linux's tmm0 or tmm interface.
The traffic is sourced from invalid ethernet MAC 00:98:76:54:32:10. The iQuery connection cannot continue.
The traffic destination is the BIG-IP Linux host, e.g. big3d iQuery server. The traffic is proxied via fastL4, e.g. ConfigSync "Local Address" is set to None. The return route is a pool route. The traffic is interrupted, e.g. a router between the iQuery server and the client is switched off for several seconds.
Increase the lasthop module's TCP idle timeout. echo 121 > /proc/sys/net/lasthop/idle_timeout/tcp
TCP connections no longer emit packets that have a source MAC address of 00:98:76:54:32:10.