The TCP implementation in (1) Linux, (2) platforms based on BSD Unix, (3) Microsoft Windows, (4) Cisco products, and probably other operating systems allows remote attackers to cause a denial of service (connection queue exhaustion) via multiple vectors that manipulate information in the TCP state table, as demonstrated by sockstress.

Multiple ethernet Network Interface Card (NIC) device drivers do not pad frames with null bytes, which allows remote attackers to obtain information from previous packets or kernel memory by using malformed packets, as demonstrated by Etherleak.

The rwho/rwhod service is running, which exposes machine status and user information.

Oversized ICMP ping packets can result in a denial of service, aka Ping o' Death.

The suidperl and sperl program do not give up root privileges when changing UIDs back to the original users, allowing root access.