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Vol. 1 · Ed. 2026
CyberGlossary
Entry № 077

Assume Breach

O que é Assume Breach?

Assume BreachA security operating philosophy that designs controls, monitoring, and architecture around the premise that an adversary is already inside the environment, prioritizing detection, containment, and recovery alongside (not instead of) prevention.


Assume Breach is a security operating philosophy popularized by Microsoft in the mid-2010s and now the default posture of mature programs and zero-trust architectures. Rather than treating prevention as the primary defense and detection as a backstop, an assume-breach program designs the environment as if the adversary has already gained a foothold and asks how detection, containment, recovery, and limiting blast-radius will hold up. Concretely this drives: network microsegmentation so lateral movement is constrained, identity-centric architecture (every request authenticated and authorized), endpoint detection and response everywhere, centralized logging with retention long enough for true-detection of slow campaigns, regular red-team and purple-team exercises against the live environment (not just labs), automated containment playbooks (isolate host, rotate keys, kill session), and recovery rehearsals (immutable backups, alternative paths to keep the business running). Assume Breach is a foundational principle of NIST 800-207 Zero Trust, the U.S. DoD Zero Trust Strategy, the U.K. NCSC Cyber Assessment Framework, and most modern security programs.

Exemplos

  1. 01

    An organization assumes any laptop may be compromised at any time and routes all administrative actions through privileged-access workstations, regardless of laptop reputation.

  2. 02

    An IR runbook for ransomware assumes initial access happened weeks earlier and triggers credential and key rotation across the affected identity tier in parallel with eradication.

Perguntas frequentes

O que é Assume Breach?

A security operating philosophy that designs controls, monitoring, and architecture around the premise that an adversary is already inside the environment, prioritizing detection, containment, and recovery alongside (not instead of) prevention. Pertence à categoria Defesa e operações da cibersegurança.

O que significa Assume Breach?

A security operating philosophy that designs controls, monitoring, and architecture around the premise that an adversary is already inside the environment, prioritizing detection, containment, and recovery alongside (not instead of) prevention.

Como funciona Assume Breach?

Assume Breach is a security operating philosophy popularized by Microsoft in the mid-2010s and now the default posture of mature programs and zero-trust architectures. Rather than treating prevention as the primary defense and detection as a backstop, an assume-breach program designs the environment as if the adversary has already gained a foothold and asks how detection, containment, recovery, and limiting blast-radius will hold up. Concretely this drives: network microsegmentation so lateral movement is constrained, identity-centric architecture (every request authenticated and authorized), endpoint detection and response everywhere, centralized logging with retention long enough for true-detection of slow campaigns, regular red-team and purple-team exercises against the live environment (not just labs), automated containment playbooks (isolate host, rotate keys, kill session), and recovery rehearsals (immutable backups, alternative paths to keep the business running). Assume Breach is a foundational principle of NIST 800-207 Zero Trust, the U.S. DoD Zero Trust Strategy, the U.K. NCSC Cyber Assessment Framework, and most modern security programs.

Como se defender contra Assume Breach?

As defesas contra Assume Breach costumam combinar controles técnicos e práticas operacionais, conforme detalhado na definição acima.

Quais são outros nomes para Assume Breach?

Nomes alternativos comuns: Breach-tolerant security, Compromise-tolerant design.

Termos relacionados