Cybersecurity Startups

Stealth Worker connects companies with qualified contractors in information security, cloud security, privacy, and compliance (including GDPR), billed at hourly rates. It operates as a marketplace for on-demand cybersecurity and compliance expertise.

3 investors

Stealthium provides a runtime observability and security platform for GPUs and AI workloads, correlating low-level GPU metrics, kernel traces, and logs into unified insights across single or multiple nodes and clusters. It monitors GPU telemetry to detect unusual usage patterns and security threats, with support for the NVIDIA software stack (drivers, CUDA, toolkits) and major AI frameworks.

3 investors

Steerlab provides AI agents that help presales teams generate tailored proposals and respond to customer questions, with an in-tool copilot and Slack bot. It also offers business intelligence tools such as a Go/No-Go agent and competitor bias detection to help teams decide which opportunities to pursue.

3 investors

Strac helps enterprises protect sensitive information during customer interactions by preventing data exposure incidents. The company builds security tools to enable secure handling of personally identifiable information without operational friction.

3 investors

Streamdal provides code-native data privacy controls embedded directly in application code to detect and prevent personally identifiable information (PII) from being exposed in databases, data streams, or pipelines. The platform offers real-time data validation and privacy enforcement for applications across multiple programming languages.

3 investors

Strivacity provides a Customer Identity and Access Management (CIAM) platform that enables organizations to deliver streamlined registration and sign-in experiences. The platform serves businesses seeking modern identity solutions.

3 investors

Styx Intel provides cybersecurity software that helps organizations protect their brand identity and reputation from external threats like executive impersonation, fake websites, and data leaks. The company focuses on digital risk protection, including brand impersonation detection and dark web monitoring.

3 investors

SubImage maps cloud, SaaS, and on-prem infrastructure into a single graph to show security teams what is exposed, misconfigured, and needs fixing first. It offers a managed CNAPP built on the open-source Cartography security graph, connecting via a read-only agentless API and integrating with SIEM, SOAR, and ticketing systems.

3 investors

Sunscreen is a company focused on cryptography, with a team specializing in cryptographic systems, high performance computing, signal processing, and computer security. Its work centers on applied cryptography and privacy-focused technology.

3 investors

Super Protocol develops confidential computing infrastructure that allows organizations to run AI workloads on sensitive data without exposing data, models, or code to infrastructure providers, collaborators, or themselves. The company uses hardware-isolated environments and cryptographic verification to remove trust dependencies from the equation.

3 investors

SuperTokens is an open-source user authentication platform that enables developers to add authentication infrastructure to their products within 15 minutes. The company provides robust user management and authentication services to engineering teams building applications, following an open core model with free base features and paid enterprise capabilities.

3 investors

SURF is an enterprise browser security platform that provides Zero Trust controls on the endpoint to secure generative AI usage, web threats, and remote access. It offers in-browser DLP for GenAI, sandboxed runtimes for autonomous AI agents, and scoped remote access for contractors and BYOD staff, serving corporate security teams as a replacement for VPN, VDI, and CASB tools.

3 investors

Surf provides an exposure management platform that connects context across a company's systems, links each security issue to its owner, and drives remediation end to end. It targets enterprise security teams, including Fortune 500 organizations, to reduce risk and close vulnerabilities.

3 investors

Syntonym develops AI-powered visual anonymization technology that removes personally identifiable information from video and image data while preserving the visual signals needed for computer vision models to function effectively. The company serves enterprises and organizations across diverse industries seeking to deploy camera-based AI systems compliantly and at scale.

3 investors

Templarbit offers a developer-oriented security platform that protects software applications from malicious activity, serving both small and large companies.

3 investors

Tensec provides secure global payment and banking services by partnering with established financial institutions worldwide. Its AI-driven platform, built on AWS infrastructure, handles cross-border payments and automates compliance controls aligned with NIST SP 800-53 standards.

3 investors

Ternoa provides a runtime security layer for continuously deployed software, using its TIP tool to monitor live systems for source mismatches, dependency compromise, and code tampering, and its CIFER tool to apply NIST-standardized post-quantum cryptography against harvest-now-decrypt-later risks. Its security operations settle on the Base blockchain, and it offers products such as Time Guardian, Athar, Unlinkable, CIFER Hub, and RWA integrations.

3 investors

thatDot's Novelty Detector is an unsupervised machine learning engine that identifies novel anomalies and threats in real-time data streams, including categorical and non-numeric data, without requiring manual training or labeled data. It serves security teams, network operations, and fraud detection teams who need to detect unknown threats and reduce false positives in high-volume data environments.

3 investors

Theorem Labs develops formal verification technology for software, producing mathematical proofs that cover a program's full behavior space, beginning with verified sandboxes designed to contain AI agents. The company targets security use cases where verification remains reliable as adversaries become more capable.

3 investors

Thoma Bravo is a software-focused private equity investment firm that acquires and invests in enterprise software and technology companies. It manages a portfolio of software businesses across areas such as cybersecurity, fintech, and enterprise applications.

3 investors

ThreatFabric provides fraud prevention software combining mobile threat intelligence and a real-time fraud risk suite to detect scams, account takeover, device takeover, and hybrid fraud across web and mobile channels. It primarily serves banks and other enterprises seeking to protect their customers' digital transactions.

3 investors

Threatcare provides educational resources about scams and fraud in plain language, covering how scams work, prevention strategies, and recovery steps for people who have been scammed. The site is aimed at general audiences seeking honest, accessible guidance on fraud awareness and response.

3 investors

ThreatMark builds a machine learning-based platform that detects digital banking fraud and threats by analyzing device, session, behavioral, and payment transaction data. It serves financial institutions seeking to counter evolving fraud while reducing false positives.

3 investors

Provides SonarQube-based code quality and security analysis across 35+ programming languages, covering first-party, AI-generated, and open source code including mobile applications. Includes software supply chain security features for managing open-source risks, detecting malicious dependencies, and generating SBOMs.

3 investors