An adversary sends a UDP datagram having an assigned value to its internet identification field (ID) to a closed port on a target to observe the manner in which this bit is echoed back in the ICMP error message. This allows the attacker to construct a fingerprint of specific OS behaviors.
The internet identification field (ID) is typically utilized for reassembling a fragmented packet. RFC791 and RFC815 discusses about IP datagrams, fragmentation and reassembly. Some operating systems or router firmware reverse the bit order of the ID field when echoing the IP Header portion of the original datagram within the ICMP error message. There are three behaviors related to the IP ID field that can be used to distinguish remote operating systems or firmware: 1) it is echoed back identically to the bit order of the ID field in the original IP header, 2) it is echoed back, but the byte order has been reversed, or it contains an incorrect or unexpected value. Different operating systems will respond by setting the IP ID field differently within error messaging.
Likelihood Of Attack
This table shows the other attack patterns and high level categories that are related to this attack pattern. These relationships are defined as ChildOf and ParentOf, and give insight to similar items that may exist at higher and lower levels of abstraction. In addition, relationships such as CanFollow, PeerOf, and CanAlsoBe are defined to show similar attack patterns that the user may want to explore.
Standard Attack Pattern - A standard level attack pattern in CAPEC is focused on a specific methodology or technique used in an attack. It is often seen as a singular piece of a fully executed attack. A standard attack pattern is meant to provide sufficient details to understand the specific technique and how it attempts to accomplish a desired goal. A standard level attack pattern is a specific type of a more abstract meta level attack pattern.
The ability to monitor and interact with network communications.Access to at least one host, and the privileges to interface with the network interface card.
A tool capable of sending/receiving UDP datagram packets from a remote system to a closed port and receive an ICMP Error Message Type 3, "Port Unreachable..
This table specifies different individual consequences associated with the attack pattern. The Scope identifies the security property that is violated, while the Impact describes the negative technical impact that arises if an adversary succeeds in their attack. The Likelihood provides information about how likely the specific consequence is expected to be seen relative to the other consequences in the list. For example, there may be high likelihood that a pattern will be used to achieve a certain impact, but a low likelihood that it will be exploited to achieve a different impact.
Bypass Protection Mechanism
[REF-33] Stuart McClure, Joel Scambray
and George Kurtz. "Hacking Exposed: Network Security Secrets & Solutions". Chapter 2: Scanning, pg. 56. 6th Edition. McGraw Hill. 2009.