CAPEC-323: TCP (ISN) Counter Rate Probe

Description

This OS detection probe measures the average rate of initial sequence number increments during a period of time. Sequence numbers are incremented using a time-based algorithm and are susceptible to a timing analysis that can determine the number of increments per unit time. The result of this analysis is then compared against a database of operating systems and versions to determine likely operation system matches.

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

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.