Multiple Vendor BSD Semaphore IPC Denial Of Service Vulnerability
A patch is available for OpenBSD at http://www.openbsd.org/errata26.html#semconfig
From the NetBSD advisory:
For NetBSD 1.4, 1.4.1, and 1.4.2:
A patch is available in
NetBSD-current since 20000527 contains all the fixes, and is not
vulnerable. Users of NetBSD-current should upgrade to a source tree
dated 20000527 or later.
From the FreeBSD Advisory:
Upgrade to FreeBSD 126.96.36.199-STABLE, 2.2.8-STABLE, 3.4-STABLE,
4.0-STABLE or 5.0-CURRENT after the correction date.
A patch is also available. See FreeBSD Advisory SA-00:19