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malicious code

nounverified·updated Aug 28, 2026

Software or firmware intended to perform an unauthorized process that will have an adverse impact on the confidentiality, integrity, or availability of a system. A virus, worm, Trojan horse, or other code-based entity that infects a host. Spyware and some forms of adware are also examples of malicious code.

MWENIST SP 800-172r3

Senses

SANS Glossary of Security Terms

Software (e.g., Trojan horse) that appears to perform a useful or desirable function, but actually gains unauthorized access to system resources or tricks a user into executing other malicious logic.

National Initiative for Cybersecurity Careers and Studies (NICCS) Cybersecurity Lexiconextended definition available

Program code intended to perform an unauthorized function or process that will have adverse impact on the confidentiality, integrity, or availability of an information system.

NIST Cybersecurity Framework

Software or firmware designed to infiltrate or damage a computer system without the owner's knowledge or consent, with the intent of compromising the confidentiality, integrity, or availability of the owner’s data, applications, or operating system. Such software typically enters a network during many business-approved activities, which results in the exploitation of system vulnerabilities. Examples include viruses, worms, Trojans (or Trojan horses), spyware, adware, and rootkits.

NISTIR 7298: Glossary of Key Information Security Terms, Revision 2

Software or firmware intended to perform an unauthorized process that will have adverse impact on the confidentiality, integrity, or availability of an information system. A virus, worm, Trojan horse, or other code-based entity that infects a host. Spyware and some forms of adware are also examples of malicious code.

NIST SP 800-171r3glossary

Software or firmware intended to perform an unauthorized process that will have an adverse impact on the confidentiality, integrity, or availability of a system. Examples of malicious code include viruses, worms, Trojan horses, spyware, some forms of adware, or other code-based entities that infect a host.

Classifications

Entity Type

Threat0%rule-basedmulti_axis_classifier_low_confidence.v1
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Sensitivity

Regulated85%llm-generatedllm:claude-haiku-4-5
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Information Class

unclassified

Variants

synonym
software threat
plural
malicious codes
possessive
malicious code's
pluralpossessive
malicious codes'