ACIA Capstone flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Annualized Loss Expectancy

ALE equals single loss expectancy multiplied by annualized rate of occurrence. It expresses expected yearly financial loss for a risk and supports comparing control cost against expected risk reduction.

Residual Risk

The risk remaining after existing controls are applied. It is compared against the organization's risk tolerance; if it exceeds tolerance, additional treatment or formal acceptance by an authorized owner is required.

Separation of Duties

A control that divides a sensitive process among different people so no single person can both authorize and execute it. It reduces fraud and error risk and is verified through a conflict matrix.

FIDO2 Authentication

A phishing-resistant standard using public-key credentials bound to the originating website. The private key stays on the authenticator, so a captured assertion cannot be replayed to a lookalike site.

Stateful versus Stateless Filtering

A stateful firewall tracks connection state and permits return traffic automatically. A stateless filter evaluates each packet independently against ordered rules, so return traffic needs an explicit rule.

Microsegmentation

A segmentation approach applying policy per workload or application rather than at the network perimeter only. It limits lateral movement because each workload accepts traffic only from explicitly permitted peers.

Shared Responsibility Model

The division of security duties between a cloud provider and its customer. The provider secures the underlying infrastructure; the customer secures data, identities, and configuration of the services used.

Security Group versus Network ACL

A security group filters at the instance level and is stateful. A network ACL filters at the subnet level, is stateless, and evaluates ordered allow and deny rules in sequence.

Digital Signature

A value produced by hashing a message and encrypting the hash with the sender's private key. Verification with the sender's public key proves integrity, authenticity, and non-repudiation.

Password Salting

Adding a unique random value to each password before hashing so identical passwords produce different hashes. It defeats precomputed rainbow tables and must be combined with a slow key derivation function.

Order of Volatility

The sequence for evidence collection from most to least volatile: processor registers and cache, memory, network state, running processes, disk, then backups and archives.

Chain of Custody

A documented record of who handled evidence, when, and for what purpose. It preserves admissibility and integrity, supported by hashing acquired images and using write blockers.

CVSS Base Score

A 0.0 to 10.0 rating of a vulnerability's intrinsic severity derived from exploitability and impact metrics. Environmental and temporal scores adjust it for local context and threat activity.

Static versus Dynamic Testing

Static analysis inspects source code without executing it and finds issues early. Dynamic analysis tests a running application from outside and can reveal runtime and configuration flaws.

Fail-Safe Defaults

A design principle stating that a failed control should deny access by default. For confidentiality-critical systems this means failing closed; safety-critical systems may require a documented safe state.

Reference Monitor

The abstract component enforcing access control, required to mediate every request, resist tampering, and be small enough to verify. It is the conceptual basis for secure kernels.

Root Cause versus Symptom

The symptom is the observed condition in a finding; the root cause explains why the control failed. Remediation addressing only the symptom leaves the underlying weakness in place.

Compensating Control

An alternative control providing risk reduction equivalent to a required control that is infeasible. It must be documented with an owner, justification, and expiry date.

Recovery Time Objective

The maximum acceptable time to restore a service after disruption, derived from business impact analysis. It drives continuity design, while the recovery point objective drives backup frequency.

Just-in-Time Access

Granting elevated privileges only for a bounded window, then revoking automatically. It reduces standing administrative rights and limits the value of a compromised privileged account.

Egress Filtering

Blocking outbound traffic to destinations not explicitly approved. It limits command-and-control communication and data exfiltration, complementing inbound perimeter controls.

Cloud Posture Management

Continuous comparison of deployed cloud configuration against a security baseline, flagging drift and misconfiguration. It is a detective control and does not itself prevent the misconfiguration.

Tokenization

Replacing a sensitive value with a non-sensitive token that maps back through a protected vault. Unlike encryption, the token has no mathematical relationship to the original value.

Indicators of Attack

Behavioral evidence of an adversary's intent and methodology rather than static artifacts. Detection based on tactics and techniques is more durable than matching hashes, addresses, or domains.

Vulnerability Remediation Priority

Ranking that combines severity, known exploitation, asset criticality, and exposure. It is more accurate than severity alone because a critical flaw on an isolated host may pose less risk.

STRIDE Threat Modeling

A design-time method enumerating spoofing, tampering, repudiation, information disclosure, denial of service, and elevation of privilege threats across each trust boundary in a data flow diagram.

Complete Mediation

A secure design principle requiring that every access request be checked against policy. Caching authorization decisions without revalidation creates a bypass path for attackers.

Defense in Depth

Layering controls with differing mechanisms so no single failure or bypass compromises the asset. Each layer assumes the others may fail, and layers should not be identical duplicates.

Exception Management

A time-bound, documented approval to deviate from a standard, naming a risk owner and compensating control. Without an expiry date the exception becomes a permanent, unmanaged risk.

Kerberos Ticket Flow

The authentication service issues a ticket-granting ticket; the ticket-granting service then issues service tickets. The key distribution center is the trust anchor for the domain.

Confused Deputy Attack

A scenario where a trusted service is tricked into acting on behalf of an unauthorized party using its own privileges. Cross-account role trust policies mitigate it with an external identifier condition.

Authenticated Encryption

An encryption mode such as GCM that provides confidentiality and integrity together. It detects tampering with ciphertext, unlike unauthenticated modes such as CBC without a separate message authentication code.