Cybersecurity Glossary

A hybrid attack is a blend of both a dictionary attack method as well as brute force attack. This means that while a dictionary attack method would include a wordlist of passwords, the brute-force attack would be applied to each possible password in that list.

HTTP is the underlying protocol used by the world wide web (www). This protocol defines how messages are formatted and transmitted on the internet and what actions web servers and browsers should take in response to various commands.

High impact is the loss of confidentiality, integrity, or availability that could be expected to have a severe or catastrophic adverse effect on organizational operations, organizational assets, individuals, other organizations, or the national security interests of the united states; (i.e., 1) causes a severe degradation in mission capability to an extent and duration that the organization is able to perform its primary functions, but the effectiveness of the functions is significantly reduced; 2) results in major damage to organizational assets; 3) results in major financial loss; or 4) results in severe or catastrophic harm to individuals involving loss of life or serious life threatening injuries).

A header refers to the additional data at the beginning of a chunk of data (or packet) being stored or transmitted. The data that follows the header is called the payload or body. Note that it is important that the header is of clear and unambiguous format to allow for parsing.

A cryptographic hash function is a kind of hash function where it is practically impossible to recreate the input data from its hash value alone. The input data is referred to as the ‘message’, and the hash value is called the ‘message digest’ or the ‘digest’. The result of this hash function can be used to validate if a larger file has been changed, without comparing the larger files. Examples of frequently used hash functions are md5 and sha1.

High availability is a failover feature to ensure availability during device or component interruptions.

Hash-based message authentication code is a message authentication code that uses a cryptographic key in conjunction with a hash function.

Hardening is also known as system hardening and refers to providing protection to a computer system at various layers such as host, application, os, user, physical levels, and all the other sublevels in between. A hardened computer system is a more secure computer system. Hardening eliminates as many risks and threats to a computer system as necessary.

Hardware is the physical component of an information system. See also software and firmware.

A hot wash is a debrief conducted immediately after an exercise or test with the staff and participants.