The Sender Policy Framework (SPF) is an essential email authentication protocol utilizing DNS TXT records to specify authorized mail servers allowed to send email for a domain, preventing email spoofing and mitigating phishing and spam campaigns by enabling recipient servers to verify the sender's IP address against the published authorized list.

Sendmail is a foundational Mail Transfer Agent (MTA) server application employing the Simple Mail Transfer Protocol (SMTP) for email transmission, often targeted in cyberattacks. Cybersecurity professionals recognize it requires careful configuration due to numerous historical vulnerabilities, including those enabling SMTP smuggling, arbitrary command injection, and link following exploits, necessitating continuous patching and monitoring.

Sensitive data encompasses all information necessitating stringent protective measures against unauthorized access, disclosure, modification, or destruction, as its compromise could severely impact individual privacy, organizational operations, financial stability, or national security interests, requiring adherence to regulatory frameworks and robust security controls.

Organizing assets by value to guide protection decisions.

Session hijacking is a sophisticated attack vector where an unauthorized entity exploits stolen or intercepted session identifiers—such as cookies or authentication tokens—to bypass security mechanisms, impersonate validated users, and gain persistent, unauthorized control over web applications, accounts, or corporate resources.

Shadow AI is the unauthorized deployment and use of AI tools and models by employees, creating significant blind spots for IT and security teams. This introduces critical risks, including sensitive data leakage, regulatory non-compliance, and operational disruption due to lack of formal oversight and governance.

Shadow IT, a significant governance challenge, describes the unauthorized deployment and use of cloud-connected applications, software, or services by employees within an organization's network perimeter without the explicit awareness, approval, or centralized oversight of the internal IT department.

Employees using personal email accounts or unauthorized tools (like Mailchimp) to send sensitive corporate data, bypassing the Secure Email Gateway. Watch out for: Corporate documents being sent to @yahoo.com or @protonmail.com addresses that belong to current employees.

The Shared Responsibility Model is a security framework that defines which tasks belong to the cloud provider and which belong to the user. While the provider (like Microsoft) secures the underlying infrastructure, the user remains responsible for their own data, identities, and security configurations. In email security, this means an organization must still implement its own phishing filters, access controls, and multi-factor authentication, even if they are using a reputable cloud email service to host their communications.

Single sign-on (SSO) is an identity and access management (IAM) mechanism allowing verified users to authenticate once, gaining secure, authorized access to multiple disparate, integrated applications and systems without re-entering credentials, often relying on protocols like SAML or OAuth 2.0.

Smishing is a social engineering attack utilizing SMS/text messages to deceive mobile device users into disclosing sensitive credentials or installing malware, thereby facilitating unauthorized access to systems or private data, representing a significant mobile threat vector.

SOC 2, or Service Organization Control 2, is a rigorous auditing framework defining standards for managing client data based on five Trust Service Criteria: security, availability, processing integrity, confidentiality, and privacy, ensuring data governance and risk management are robust for service organizations.

The human element represents the most critical vulnerability in cybersecurity defense, as malicious social engineering tactics exploit the inherent tendency of users to fail to recognize and appropriately respond to sophisticated deceptive attack vectors.

Social media archiving involves the secure, systematic capture and immutable preservation of all enterprise social media data, including content, context, and associated metadata, ensuring compliance with regulatory mandates, enabling robust e-discovery for litigation, and maintaining comprehensive audit trails for forensic analysis and information governance.

Social media protection solutions are specialized cybersecurity tools designed to mitigate risks associated with corporate social media presence, encompassing unauthorized access prevention, the detection and remediation of brand impersonation accounts, executive spoofing, and the critical filtering of malicious or harmful content targeting customers.

Social media platforms facilitate connectivity and content sharing, yet excessive disclosure or inadequate verification against malicious entities, such as impostors, significantly elevates the risk of compromise to both corporate assets and individual user accounts, necessitating robust security protocols.

A Software-Defined Perimeter (SDP) is a zero-trust security methodology that dynamically controls access to networked resources based on verified user identity and device posture. It reduces the threat surface by creating an invisible, virtual boundary around application infrastructure, ensuring users only access authorized applications, thereby minimizing cyber risk and third-party exposure.

Software as a Service (SaaS) is a delivery model that allows users to access cloud-based applications via a web browser without needing to install software locally. Most modern email platforms, such as Gmail and Microsoft 365, are SaaS tools. While SaaS provides flexibility and automatic updates, it also requires organizations to trust a third party with their data. This shift necessitates robust identity management and third-party risk assessments to ensure that the provider's security standards meet the organization’s compliance requirements.

Unsolicited Commercial Email (UCE), commonly known as spam, is the abuse of electronic messaging systems involving the indiscriminate sending of bulk, unwanted messages for commercial purposes. UCE poses a significant cybersecurity risk by often containing malicious content, phishing schemes, and links used to spread malware, facilitate identity theft, and compromise digital infrastructures.

Spear phishing is a highly personalized and targeted type of social engineering attack that specifically aims at individuals or organizations, often via malicious emails, texts, or calls. Attackers research targets to craft credible, fraudulent messages from seemingly trusted sources, intending to steal credentials, deploy malware/ransomware, or acquire financial data undetected.

In cybersecurity, spoofing is the deceptive practice where an attacker deliberately falsifies data or communication origins to masquerade as a trusted entity, thereby gaining unauthorized access or disseminating malware within a network infrastructure.

Spyware is malicious software installed secretly to monitor and collect sensitive data—such as keystrokes, network traffic, authentication credentials, and financial information—often resulting in data theft, identity fraud, and system disruption, leveraging methods like Trojans, malicious BHOs, or system monitor techniques.

Stale data, within a cybersecurity context, constitutes digital information that is demonstrably outdated, unused, or contextually irrelevant, yet persistently resides within active storage systems. Its continued presence significantly expands the organization's attack surface and introduces compliance risks, potentially leading to unauthorized data exposure or operational inefficiency.

Finding an abandoned subdomain (e.g., dev.old-brand.com) that still has your company's SPF record and using it to send "trusted" phishing mail. Watch out for: Spikes in outbound email from subdomains that were officially retired or haven't been used by the company in years.

Comprehensive intellectual property (IP) and data protection mandates a strategy extending beyond conventional system cybersecurity measures, requiring the implementation of holistic security controls, policies, and continuous monitoring to effectively mitigate threats and safeguard sensitive organizational assets against escalating theft risks.

A supply chain attack is a sophisticated vector compromising an organization's security by surreptitiously injecting malicious code, libraries, or components into legitimate software or hardware products, often bypassing established security controls and targeting trusted third-party dependencies.

Supply chain security is a multi-layered, risk-management approach encompassing strategies, protocols, and technologies—including both physical and digital cybersecurity measures—to protect an organization's entire network of resources, processes, and third-party partnerships from malicious attacks, unauthorized access, and the introduction of compromised hardware or software components.

Synthetic identity fraud is a sophisticated financial crime involving the fabrication of an identity, often a "Frankenstein ID," by combining elements of real, stolen personally identifiable information (PII)—like a SSN—with fictitious data (name, address). This complexity makes it difficult to detect with traditional monitoring systems.

Transport Layer Security (TLS) is a cryptographic protocol designed to provide secure communication over a computer network. In email, TLS is used to encrypt messages while they are moving between servers, preventing "man-in-the-middle" attackers from reading or stealing the contents. While TLS protects the data in transit, it does not protect the email once it has arrived at its destination. Therefore, it must be used as part of a broader encryption strategy that includes protecting data at rest to meet compliance standards.

Tactics, Techniques, and Procedures (TTPs) are the high-level strategies (tactics), intermediate methods (techniques), and detailed sequences of actions (procedures) utilized by threat actors to execute a cyberattack. Understanding TTPs is fundamental for cybersecurity professionals to develop robust defense mechanisms, enhance threat intelligence, and optimize incident response plans against adversaries.

Following an authorized person into a secure physical area without permission.

A tailgating attack, also known as piggybacking, is a physical security breach where an unauthorized individual gains access to restricted, secured premises by immediately following an authorized person through a checkpoint, often exploiting human trust or distraction without presenting valid credentials.

Telemetry, for cybersecurity professionals, is the critical, continuous process of gathering, correlating, and analyzing data from diverse sources—including endpoints, cloud environments, and security logs—to gain broad environmental visibility, enabling swift threat detection, incident response, and proactive security measures.

A thin client is a network-dependent endpoint device leveraging a centralized server for all services and data processing, offering organizations streamlined security, simplified management, and reduced risk due to minimal local storage and attack surface.

A threat actor is an individual or group, internal or external, that instigates risks and possesses the capability and motivation—often financial, political, or thrill-seeking—to exploit system vulnerabilities using tactics like malware and phishing to compromise data security and perpetrate cyberattacks.

Threat intelligence is the analysis of adversaries, their motivations, capabilities, and indicators of compromise, providing actionable context to cybersecurity professionals. This crucial data enables proactive defense, swift incident response, and strategic risk management to protect organizational assets from evolving cyber threats.

TOTP is a critical component of two-factor authentication (2FA), adhering to the OATH standard, which generates a temporary, time-constrained passcode using a shared secret key and cryptographic functions, offering a significantly superior and more secure mechanism than event-based HOTP against modern cybersecurity threats.

Malware that looks like a legitimate program but is actually a trap.

A Trojan Horse is a class of malware that deceptively masquerades as benign or desirable software to infiltrate a system, gaining unauthorized access and executing malicious payloads under the pretense of legitimacy, often enabling remote control or data exfiltration.

Typosquatting, or URL hijacking, is a social engineering attack where malicious actors register domain names that are misspellings of legitimate sites to deceive users into visiting fraudulent pages. This technique is often used for phishing, malware delivery, or data theft by exploiting common typographical errors like transpositions or omissions.

User and Entity Behavior Analytics (UEBA) is a sophisticated cybersecurity methodology leveraging machine learning and statistical analysis to detect anomalous activities, identify potential insider threats, and reveal external attacks by baselining normal behavior across users, applications, and endpoints.

Examining a web address to see if it is linked to malicious activity.

Unstructured data, lacking a predefined data model in various formats like emails, documents, and videos, is a significant challenge for cybersecurity professionals. Its complexity, volume, and sprawl often lead to lack of visibility, making governance and access control difficult, thus heightening data breach risk and compliance violations.

A technique where the human-readable VBA source code is removed from a Word/Excel doc, leaving only the "compiled" code to bypass static security scanners. Watch out for: Documents that appear to have "No Macros" in a basic search but execute malicious code when detonated in a secure sandbox.

A Virtual Private Network (VPN) establishes a secure, encrypted tunnel over a public network, masking the user's IP address and securing data transmission confidentiality and integrity, which is critical for remote access and mitigating man-in-the-middle attacks.

Tools used to scan assets for malicious software like viruses.

Vishing, a prevalent social engineering tactic, utilizes phone calls and manipulated voice communication technology to deceptively acquire confidential data from victims, bypassing traditional network security protocols and constituting a significant vector for cybersecurity risk and fraud.

A vulnerability in a cybersecurity context is a critical flaw or weakness, originating in the design, operational processes, implementation, or system management, that constitutes an exploitable entry point enabling an adversary to execute unauthorized access, information disclosure, or cause detrimental system harm.

WannaCry was a globally catastrophic 2017 ransomware campaign leveraging the EternalBlue exploit against Windows SMB vulnerabilities, rapidly encrypting corporate data across numerous sectors and demanding Bitcoin payment, highlighting critical patching failures in unmanaged systems worldwide.

A watering hole attack is a highly focused cyber-attack where adversaries infect websites frequently visited by a target group, such as a specific industry or organization, in order to compromise unsuspecting users when they navigate to the legitimate, but now malicious, site.

Infecting a website that a specific group of people visits often to infect the visitors.

A web proxy server is an intermediate system used by organizations primarily for security, by masking internal IP addresses, and for performance optimization, by caching content to reduce bandwidth consumption and enhance data transfer efficiency.

Web security is the comprehensive practice of protecting an organization’s data, network resources, and systems against online threats like malware, phishing, data theft, and sophisticated attacks (e.g., DDoS, session hijacking), utilizing technologies such as WAFs and security awareness programs.

A phishing attack targeted specifically at high-profile executives.

Whaling is a highly targeted, advanced social engineering phishing attack aimed exclusively at senior executives, like C-level personnel, leveraging their high-level access to sensitive corporate data and significant financial assets for malicious gain.

A list of approved senders or domains that are always allowed through.

Wi-Fi, standardized under IEEE 802.11 protocols, enables wireless local area networking (WLAN) using radio waves for connectivity. This technology organizes data into 802.11 frames, similar to Ethernet, utilizing MAC addresses for routing, demanding specific security implementations to protect data integrity and network access.

Malware that spreads copies of itself between computers without human interaction.

Manually setting the X-Priority: 1 (Highest) header to force a "Red Flag" icon in the recipient's inbox, increasing the psychological pressure to click. Watch out for: Emails from external senders that are marked as "High Priority" but involve mundane tasks or generic "Security Alerts."

A known flaw that does not have a fix or patch yet.

Zero Trust is a security paradigm where no user or device, whether inside or outside the network perimeter, is inherently trusted. It requires continuous verification of every access request based on context, strong authentication, authorization, and validation of the user, device, and service prior to granting minimum necessary access.

A zero-day vulnerability is a newly discovered, unknown security flaw in software or hardware for which the developer has not yet created a patch or mitigation. This critical exposure is actively exploited by threat actors before security professionals are aware, demanding immediate, high-priority remediation actions.

Zeus is a foundational banking trojan, notorious for its longevity and success in credential harvesting. Originating as one of the oldest forms of financial malware, its code base was ultimately sold, leading to the proliferation of numerous subsequent variants that continue to pose threats to global financial institutions and users.