WebVoyager — agentic threat model
WebVoyager is a highly autonomous, multimodal web agent that executes tasks directly on real-world websites. Its primary risk stems from executing unmediated browser actions based on untrusted web content, making it highly susceptible to visual and textual prompt injection attacks.
OWASP AIVSS score rationale
| Autonomy of Action | 0.90 | |
| Goal-Driven Planning | 0.80 | |
| Self-Modification | 0.10 | |
| Dynamic Tool Use | 0.80 | |
| Persistent Memory | 0.20 | |
| Contextual Awareness | 0.80 | |
| Dynamic Identity | 0.30 | |
| Multi-Agent Interactions | 0.00 | |
| Non-Determinism | 0.70 | |
| Opacity & Reflexivity | 0.60 |
Scored with the canonical OWASP AIVSS formula (AIVSS calculator reference); agentic risk factors estimated from the agent’s described capabilities.
MAESTRO 7-layer threat model
Per-layer threats for this agent. Layers tagged “not certain from listing” are general, caveated commentary where the public description didn’t pin that layer.
Uses Large Multimodal Models (LMMs) to process both visual screenshots and text. This makes the agent highly vulnerable to indirect prompt injection via malicious web content, including adversarial images (visual prompt injection) and hidden text on target websites.
Not certain from the listing — No details are provided regarding data operations, vector databases, or training data. However, dynamically processing live web data poses risks of data poisoning if the agent caches or stores retrieved web content for future context.
Employs Set-of-Mark Prompting and self-healing automation to plan and execute actions. The primary threat is tool misuse, where the browser automation tool is manipulated by adversarial web elements into performing unintended actions like unauthorized form submissions or clicks.
Not certain from the listing — The deployment infrastructure and sandboxing mechanisms are not specified. If the browser automation runs without strict containerization, a compromised session could lead to local file access or remote code execution on the host.
Not certain from the listing — There is no mention of guardrails, logging, or observability features. Without real-time monitoring of the agent's browser actions, malicious or anomalous behaviors on third-party sites may go undetected.
Not certain from the listing — No security, compliance, or identity management controls are described. Operating on real-world websites implies the agent may handle sensitive user sessions or credentials, which requires robust encryption and access controls.
Not certain from the listing — The agent is described as a standalone web navigator with no explicit multi-agent or ecosystem integrations. The primary ecosystem risk would arise if other automated systems rely on WebVoyager's outputs without verification.
MAESTRO — the 7-layer agentic threat-modeling framework (Cloud Security Alliance / Ken Huang).
These scores are auto-generated from public information (the agent's own listing, docs, and repository) using the canonical OWASP AIVSS formula and the MAESTRO framework — an estimate for guidance, not a penetration test, audit, or certification. See the scoring methodology. Are you the vendor? Factual corrections are free.