Glossary
Cybersecurity & IT glossary.
Fifty terms defined in plain language. Cybersecurity operations, compliance frameworks, architecture patterns, and the operational metrics that actually show up in SLAs. Written by practitioners who use these terms daily rather than glossary-style vendor boilerplate.
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All terms, alphabetical
BEC (Business Email Compromise)
SecurityAn attack in which an adversary gains access to or impersonates a legitimate business email account to initiate fraudulent wire transfers, redirect payments, or extract sensitive data.
BEC typically starts with credential theft via phishing, followed by the attacker operating as the user: reading mail, creating forwarding rules, and sending fraudulent wire instructions. FBI IC3 reports BEC as one of the highest-dollar-loss cybercrime categories annually.
CA AB 2013 (Generative AI Training Data Transparency)
ComplianceCalifornia Assembly Bill 2013 (effective January 2026) requires generative-AI providers to publish a high-level summary of training data used, including sources, modifications, and inclusion of personal information. Applies to commercial deployments serving California residents.
CMMC (Cybersecurity Maturity Model Certification)
ComplianceUS Department of Defense framework requiring defense industrial base (DIB) contractors to achieve certified cybersecurity posture at one of three levels. Level 2 applies to most contractors handling Controlled Unclassified Information (CUI).
Colorado AI Act (SB 24-205)
ComplianceFirst comprehensive US state AI law (effective February 2026). Imposes obligations on developers and deployers of 'high-risk AI systems' that make or substantially inform 'consequential decisions' across nine categories: employment, healthcare, financial services, education, housing, insurance, legal services, criminal justice, and government services.
Key obligations: impact assessment, consumer notice with right-to-appeal, opt-out from substantial-factor automated decisions, risk-management policy aligned to NIST AI RMF, annual review. Connecticut, Texas, and Virginia have advanced similar bills.
CSPM (Cloud Security Posture Management)
SecurityContinuous discovery, assessment, and remediation of security misconfigurations and compliance gaps across cloud environments (AWS, Azure, GCP).
CSPM catches the configuration drift that causes most cloud data breaches: public S3 buckets, exposed storage accounts, over-permissioned IAM roles, and unencrypted resources. It's table stakes for any regulated cloud deployment.
CUI (Controlled Unclassified Information)
ComplianceUS government information that requires safeguarding under specific rules but is not classified. Defense contractors handling CUI are required to meet NIST SP 800-171 controls and, under CMMC, achieve Level 2 certification.
DFARS 7012
ComplianceDefense Federal Acquisition Regulation Supplement clause 252.204-7012 requires DoD contractors to implement NIST SP 800-171 controls and report cyber incidents within 72 hours.
DLP (Data Loss Prevention)
SecurityTechnology controls that detect and prevent sensitive data from being exfiltrated, whether via email, cloud storage, removable media, or web uploads. Policies are driven by data classification.
EDR (Endpoint Detection and Response)
SecurityEndpoint security platform that collects behavioral telemetry from workstations and servers, detects malicious activity, and enables forensic investigation and response.
EDR is the successor to traditional antivirus. Leading platforms include CrowdStrike Falcon, SentinelOne Singularity, Microsoft Defender for Endpoint, and Palo Alto Cortex XDR. EDR feeds naturally into XDR and SOAR workflows.
FedRAMP (Federal Risk and Authorization Management Program)
ComplianceUS federal program that standardizes security assessment and authorization for cloud services used by federal agencies. FedRAMP authorization levels are Low, Moderate, and High.
FFIEC CAT (Cybersecurity Assessment Tool)
ComplianceAssessment framework from the Federal Financial Institutions Examination Council used by banks and credit unions to evaluate cybersecurity preparedness across five maturity domains.
FIDO2
SecurityOpen authentication standard enabling passwordless, phishing-resistant authentication using public-key cryptography. WebAuthn is the W3C browser API that exposes FIDO2 to web apps.
FIDO2 is the authentication standard that can actually stop modern phishing. Passwords and SMS-based MFA remain phishable; FIDO2 hardware tokens and platform authenticators are not.
FinOps
ArchitectureDiscipline of running cloud environments with business-aware cost management, combining engineering, finance, and business stakeholders around cloud spend decisions.
GDPR (General Data Protection Regulation)
ComplianceEuropean Union regulation governing the processing of personal data of EU residents. Requires lawful basis for processing, data subject rights, breach notification within 72 hours, and DPO appointment for qualifying organizations.
GLBA (Gramm-Leach-Bliley Act)
ComplianceUS law requiring financial institutions to protect the security and confidentiality of customer information. The Safeguards Rule (FTC, updated 2021) specifies technical and procedural controls required.
HIPAA Security Rule
ComplianceUS regulation requiring covered entities and business associates to implement administrative, physical, and technical safeguards to protect electronic protected health information (ePHI).
HSM (Hardware Security Module)
ArchitectureTamper-resistant hardware device that performs cryptographic operations and protects private keys. FIPS 140-2 and 140-3 define the validation standards.
IAM (Identity and Access Management)
SecurityFramework of policies and technologies that ensures the right individuals (and services) access the right resources at the right time for the right reasons. Core components: authentication, authorization, identity governance, and privileged access.
ISO/IEC 42001 (AI Management System)
ComplianceInternational standard for AI management systems (published December 2023). The AI counterpart to ISO/IEC 27001 for information security. Certifiable through accredited bodies; rapidly becoming the procurement standard for US enterprise customers buying from AI-deploying vendors.
Annex A control set covers AI policy, risk assessment, treatment, internal audit, management review, lifecycle controls, third-party AI, data quality, and intended-use documentation. Pairs naturally with NIST AI RMF in US contexts.
ITDR (Identity Threat Detection and Response)
SecuritySecurity category focused on detecting and responding to identity-based attacks: credential theft, token theft, privilege escalation, and suspicious authentication patterns.
MDR (Managed Detection and Response)
SecurityOutsourced service that combines an EDR/XDR platform with 24/7 human analyst operations, threat hunting, and pre-authorized containment actions.
Microsegmentation
ArchitectureNetwork security approach that creates fine-grained segmentation boundaries between individual workloads or applications, restricting east-west traffic through policy rather than through physical or VLAN-level separation.
MITRE ATT&CK
SecurityPublicly available framework of adversary tactics and techniques observed in real-world attacks. Used by SOC teams to structure detection content, threat hunting, and incident scoping.
MSP (Managed Service Provider)
IT OperationsThird-party provider that manages a customer's IT infrastructure and end-user systems under a recurring service contract, typically with a defined SLA.
MSSP (Managed Security Service Provider)
SecurityThird-party provider that delivers security operations services (SOC, SIEM, MDR, compliance) to customers under a recurring service contract.
MTTC (Mean Time to Contain)
MetricsAverage time from when an incident is detected to when the adversary's active activity is halted or contained. A core operational metric for SOC and MDR programs.
Best-in-class MTTC for pre-authorized containment operates under 15 minutes. Typical MSSP MTTC with manual approval loops runs 45-90 minutes. The gap is the primary outcome differentiator between MDR providers.
MTTD (Mean Time to Detect)
MetricsAverage time from when an adversary action starts to when a security detection fires. Mature SOC operations target MTTD under 5 minutes for high-severity activity.
MTTR (Mean Time to Resolve)
MetricsAverage time from incident detection to full resolution, including containment, eradication, and recovery. In MSP operations, MTTR typically covers production-impacting incidents end-to-end.
NDR (Network Detection and Response)
SecuritySecurity category focused on analyzing network traffic to detect threats, including lateral movement, command-and-control communications, and data exfiltration patterns.
NIST AI RMF (AI Risk Management Framework)
ComplianceVoluntary US federal framework (NIST AI RMF 1.0, January 2023) organizing AI risk management around four functions: Govern, Map, Measure, Manage. Companion GPAI Profile (2024) adds Foundation Model and generative AI controls.
While voluntary, NIST AI RMF is rapidly becoming the procurement and insurance baseline for US AI deployments. Most regulated SMBs use it as the foundation that other frameworks (Colorado AI Act, NYC LL144, sector overlays) layer onto.
NIST CSF (Cybersecurity Framework)
ComplianceWidely adopted framework from the US National Institute of Standards and Technology that organizes cybersecurity activities across six functions: Govern, Identify, Protect, Detect, Respond, and Recover. CSF 2.0 (2024) added the Govern function.
NIST SP 800-171
ComplianceNIST publication specifying 110 security requirements for protecting Controlled Unclassified Information (CUI) in nonfederal systems and organizations. Required by DFARS 7012 and CMMC Level 2.
NIST SP 800-207 (Zero Trust Architecture)
ArchitectureNIST publication defining the architectural principles of Zero Trust. The authoritative reference document for Zero Trust implementations, including the seven tenets that any serious Zero Trust program maps back to.
NOC (Network Operations Center)
IT OperationsCentralized facility (physical or virtual) where engineers monitor, manage, and respond to IT infrastructure issues. The operational analog of a SOC, focused on availability and performance rather than security.
NYC Local Law 144 (Automated Employment Decision Tools)
ComplianceNew York City ordinance (effective July 2023) requiring annual independent bias audits of any automated employment decision tool used to screen NYC-resident candidates or employees. Audit results must be published publicly, and candidates must be notified of AED tool use 10 business days before evaluation.
Applies based on candidate location, not employer headquarters. Penalties: $500 per first violation, $1,500 per subsequent. Has spawned similar bills in California, Illinois, and federal proposals.
NYDFS Part 500
ComplianceNew York Department of Financial Services cybersecurity regulation applying to banks, insurance companies, and other financial services institutions operating in NY. Requires written cybersecurity program, CISO designation, and incident notification within 72 hours.
PAM (Privileged Access Management)
SecurityCategory of controls for managing access to privileged accounts: vaulting credentials, enabling just-in-time elevation, recording privileged sessions, and enforcing approval workflows.
PCI-DSS v4.0.1
CompliancePayment Card Industry Data Security Standard, version 4.0 (effective March 2024 enforcement). Mandatory for organizations that store, process, or transmit cardholder data. Requires annual assessment with scope and control rigor tied to transaction volume.
Phishing-resistant MFA
SecurityMulti-factor authentication methods that cannot be compromised by phishing or adversary-in-the-middle attacks. Includes FIDO2 hardware tokens, platform authenticators using WebAuthn, and smart cards. Excludes SMS codes and TOTP pushed over phishable channels.
RACI matrix
IT OperationsResponsibility assignment model documenting who is Responsible, Accountable, Consulted, and Informed for each task or decision. Critical for vendor contracts and IR runbooks where role ambiguity creates response delays.
Ransomware
SecurityMalware that encrypts victim data (and sometimes exfiltrates it first) to extort payment for decryption and non-disclosure. Modern ransomware operations typically exfiltrate data before encryption and demand two separate payments.
RPO (Recovery Point Objective)
MetricsMaximum tolerable data loss measured in time, for example 15 minutes or 1 hour. Drives backup frequency and replication design for business continuity planning.
RTO (Recovery Time Objective)
MetricsMaximum tolerable downtime from disruption to restored operation, for example 4 hours or 24 hours. Drives recovery architecture decisions (active-active, pilot-light, backup-and-restore).
SASE (Secure Access Service Edge)
ArchitectureArchitectural model that converges network connectivity (SD-WAN) and security services (SWG, ZTNA, CASB, FWaaS) into a single cloud-delivered service.
SIEM (Security Information and Event Management)
SecurityPlatform that aggregates and correlates log and event data across an enterprise to detect security issues. Major platforms: Microsoft Sentinel, Splunk Enterprise Security, IBM QRadar, Elastic Security.
SOAR (Security Orchestration, Automation, and Response)
SecurityPlatform that automates security workflows and response playbooks, integrating with SIEM, EDR, ticketing, and other tools to reduce manual analyst work on repetitive investigation and containment tasks.
SOC (Security Operations Center)
SecurityFacility and team responsible for 24/7 monitoring, detection, investigation, and response to cybersecurity events. Can be in-house, fully outsourced, or hybrid.
SOC 2 Type II
ComplianceAttestation report from an independent auditor on the design and operating effectiveness of controls at a service organization over a period of time (typically 6-12 months). Based on the AICPA Trust Services Criteria (2017).
Speculation Rules API
ArchitectureBrowser API (Chromium) that lets pages declare prefetch or prerender rules for likely next navigations, improving perceived performance by starting page loads before the user clicks.
SR 11-7 (Federal Reserve Model Risk Management)
ComplianceFederal Reserve Supervision and Regulation Letter 11-7 (2011) + OCC Bulletin 2011-12 โ model risk management guidance for US banking organizations. Defines 'model' broadly; explicitly extended to generative AI and Foundation Models in 2024 supervisory guidance.
Three pillars: model development standards, model validation, governance and controls. AI deployments in pricing, underwriting, fraud detection, AML, and credit decisioning are squarely in scope. NYDFS Part 500 ยง500.17 incident reporting includes AI-mediated incidents.
System Integration
IT OperationsDiscipline of connecting disparate enterprise applications (CRM, ERP, billing, HR, custom platforms) into a coherent operational whole through APIs, middleware, event streaming, or data synchronization.
Threat hunting
SecurityProactive security activity in which analysts hypothesize adversary behavior and search environment data for evidence of intrusions that automated detection did not surface. Complements alert-driven SOC operations.
TN ELVIS Act (Tennessee Voice and Likeness Cloning)
ComplianceTennessee Ensuring Likeness, Voice, and Image Security Act (effective July 2024) creates civil cause of action for unauthorized AI cloning of an individual's voice or likeness. First US state law specifically targeting deepfakes and AI-generated voice replicas.
Triggered by Nashville music industry concerns. Damages: actual + statutory + injunctive relief. Has spawned similar bills in California, Illinois, and federal NO FAKES Act.
vCISO (Virtual CISO)
IT OperationsFractional or interim executive security leadership arrangement. Provides strategic direction, board reporting, regulatory interface, and incident leadership without a full-time CISO hire.
XDR (Extended Detection and Response)
SecuritySecurity platform that correlates telemetry across multiple domains (endpoint, network, identity, cloud, SaaS) to detect attacks that span those domains. Typically delivered as a platform that unifies EDR, NDR, and ITDR signals.
Zero Trust Architecture
ArchitectureSecurity architecture that eliminates implicit trust based on network location and instead requires continuous verification of every access request against identity, device health, and risk signals.
ZTNA (Zero Trust Network Access)
ArchitectureAccess technology that replaces traditional VPN by creating encrypted, policy-enforced connections between users and specific applications rather than granting broad network access. Leading platforms include Zscaler Private Access, Palo Alto Prisma Access, Cloudflare Access, and Microsoft Entra Private Access.
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Beyond the definitions
Blog
Long-form writing on the terms above โ strategy, implementation, real-world cases.
OpenResources Library
Checklists, runbooks, and templates for the practices these terms describe.
OpenFree Tools
Quick self-assessments mapped to the concepts in the glossary.
OpenServices
The managed services that operationalize these concepts in your environment.
OpenSecurity Services
MDR, vCISO, SOC, IR โ the operational disciplines behind the security terms.
OpenAI Governance
The newest discipline โ NIST AI RMF, Colorado AI Act, vendor risk for AI.
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