CAPEC-324: TCP (ISN) Sequence Predictability Probe

Description

This type of operating system probe attempts to determine an estimate for how predictable the sequence number generation algorithm is for a remote host. Statistical techniques, such as standard deviation, can be used to determine how predictable the sequence number generation is for a system. This result can then be compared to a database of operating system behaviors to determine a likely match for operating system and version.

Extended Description

During a UDP scan, a datagram is sent to a target port. If an 'ICMP Type 3 Port unreachable' error message is returned then the port is considered closed. Different types of ICMP messages can indicate a filtered port. UDP scanning is slower than TCP scanning. The protocol characteristics of UDP make port scanning inherently more difficult than with TCP, as well as dependent upon ICMP for accurate scanning. Due to ambiguities that can arise between open ports and filtered ports, UDP scanning results often require a high degree of interpretation and further testing to refine. In general, UDP scanning results are less reliable or accurate than TCP-based scanning.

Severity :

Low

Possibility :

Medium

Type :

Detailed

Relationships with other CAPECs

This table shows the other attack patterns and high level categories that are related to this attack pattern.

CAPEC-312: Active OS Fingerprinting Active OS Fingerprinting

Prerequisites

This table shows the other attack patterns and high level categories that are related to this 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.

Skills required

This table shows the other attack patterns and high level categories that are related to this attack pattern.

Taxonomy mappings

Mappings to ATT&CK, OWASP and other frameworks.

Resources required

A tool capable of sending and receiving packets from a remote system.

Related CWE

A Related Weakness relationship associates a weakness with this attack pattern. Each association implies a weakness that must exist for a given attack to be successful.

CWE-200: Exposure of Sensitive Information to an Unauthorized Actor

Visit http://capec.mitre.org/ for more details.