The securelevels implementation in NetBSD 2.1 and earlier, and Linux 2.6.15 and earlier, allows local users to bypass time setting restrictions and set the clock backwards by setting the clock ahead to the maximum unixtime value (19 Jan 2038), which then wraps around to the minimum value (13 Dec 1901), which can then be set ahead to the desired time, aka "settimeofday() time wrap."
imake in NetBSD before 2.0.3, NetBSD-current before 12 September 2005, certain versions of X.Org, and certain versions of XFree86 allows local users to overwrite arbitrary files via a symlink attack on the temporary file for the file.0 target, which is used for a pre-formatted manual page.
NetBSD 1.6, NetBSD 2.0 through 2.1, and NetBSD-current before 20051031 allows local users to gain privileges by attaching a debugger to a setuid/setgid (P_SUGID) process that performs an exec without a reset of real credentials.
Integer overflow in the FreeBSD compatibility code (freebsd_misc.c) in NetBSD-current, NetBSD-3, NetBSD-2.0, and NetBSD-2 before 20050913; and NetBSD-1.6 before 20050914; allows local users to cause a denial of service (heap corruption or system crash) and possibly gain root privileges.
verifiedexecioctl in verified_exec.c in NetBSD 2.0.2 calls NDINIT with UIO_USERSPACE rather than UID_SYSSPACE, which removes the functionality of the verified exec kernel subsystem and might allow local users to execute Trojan horse programs.
NetBSD 2.0 before 2.0.4, 2.1 before 2.1.1, and 3, when the kernel is compiled with "options DIAGNOSTIC," allows local users to cause a denial of service (kernel assertion panic) via a negative linger time in the SO_LINGER socket option.
The (1) clcs and (2) emuxki drivers in NetBSD 1.6 through 2.0.2 allow local users to cause a denial of service (kernel crash) by using the set-parameters ioctl on an audio device to change the block size and set the pause state to "unpaused" in the same ioctl, which causes a divide-by-zero error.