The chrp_show_cpuinfo function (chrp/setup.c) in Linux kernel 2.4.21 through 2.6.18-53, when running on PowerPC, might allow local users to cause a denial of service (crash) via unknown vectors that cause the of_get_property function to fail, which triggers a NULL pointer dereference.

The perfmonctl system call (sys_perfmonctl) in Linux kernel 2.4.x and 2.6 before 2.6.18, when running on Itanium systems, does not properly track the reference count for file descriptors, which allows local users to cause a denial of service (file descriptor consumption).

Multiple integer overflows in Sbus PROM driver (drivers/sbus/char/openprom.c) for the Linux kernel 2.4.x up to 2.4.27, 2.6.x up to 2.6.7, and possibly later versions, allow local users to execute arbitrary code by specifying (1) a small buffer size to the copyin_string function or (2) a negative buffer size to the copyin function.