FreeBSD Security Advisory FreeBSD-SA-05:09 – When running on processors supporting Hyper-Threading Technology, it is possible for a malicious thread to monitor the execution of another thread.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/38548/FreeBSD-SA-05-09.htt.txt
Source: https://packetstormsecurity.com/files/38548/FreeBSD-SA-05-09.htt.txt.html