The pf_test_rule function in OpenBSD Packet Filter (PF), as used in OpenBSD 4.2 through 4.5, NetBSD 5.0 before RC3, MirOS 10 and earlier, and MidnightBSD 0.3-current allows remote attackers to cause a denial of service (panic) via crafted IP packets that trigger a NULL pointer dereference during translation, related to an IPv4 packet with an ICMPv6 payload.

The Korn shell (aka mksh) before R33d on MirOS (aka MirBSD) does not flush the tty's I/O when invoking mksh in a new terminal, which allows local users to gain privileges by opening a virtual terminal and entering command sequences, which might later be executed in opportunistic circumstances by a different user who launches mksh and specifies that terminal with the -T option.