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).

Buffer overflow in NFS readlink handling in the Linux Kernel 2.4 up to 2.4.31 allows remote NFS servers to cause a denial of service (crash) via a long symlink, which is not properly handled in (1) nfs2xdr.c or (2) nfs3xdr.c and causes a crash in the NFS client.

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.

The experimental IP packet queuing feature in Netfilter / IPTables in Linux kernel 2.4 up to 2.4.19 and 2.5 up to 2.5.31, when a privileged process exits and network traffic is not being queued, may allow a later process with the same Process ID (PID) to access certain network traffic that would otherwise be restricted.

IRC connection tracking helper module in the netfilter subsystem for Linux 2.4.18-pre9 and earlier does not properly set the mask for conntrack expectations for incoming DCC connections, which could allow remote attackers to bypass intended firewall restrictions.