In the Linux kernel, the following vulnerability has been resolved:
net/sched: act_ct: fix ref leak when switching zones
When switching zones or network namespaces without doing a ct clear in between, it is now leaking a reference to the old ct entry. That's because tcfctskbnfctcached() returns false and tcfctflowtablelookup() may simply overwrite it.
The fix is to, as the ct entry is not reusable, free it already at tcfctskbnfctcached().