Proactively secure MCP Servers with Levo’s MCP Security Testing

MCP vulnerability testing identifies specific weaknesses in MCP servers that can be exploited. It focuses on repeatable vulnerability classes such as token leakage, authorization flaws, unsafe command execution, and context injection. The best vulnerability testing validates impact, not just detection. That means proving whether a finding can affect downstream tools, data access, or autonomous workflows, so remediation focuses on what can actually break production. Levo’s MCP Security Testing covers core MCP vulnerability classes and validates failure behavior under realistic conditions. It prioritizes actionable findings by testing with real authentication states and workflow context, not shallow scans.

MCP server DAST is dynamic application security testing applied to running MCP servers. Instead of scanning code, it tests the live server by sending payloads and observing runtime behavior. For MCP, DAST is valuable because many issues only show up during tool execution and chained calls. It can reveal injection paths, unsafe execution behavior, and weak access controls that unit tests or static checks often miss. Levo runs security testing against MCP servers in realistic runtime conditions, including authentication and workflow boundaries. It also supports continuous validation so new servers and changes do not silently expand the attack surface.

An MCP security scanner is a tool that assesses MCP servers for security weaknesses and unsafe execution patterns. It should validate authentication and authorization, including safe failure behavior when access is denied. It should also test for prompt and context injection, because MCP servers turn language into action. It should test tool poisoning, because compromised tool outputs can quietly manipulate workflows. It should validate secrets handling, because token exposure can inherit access to downstream systems. Levo’s MCP Security Testing automates these validations and keeps them current as MCP usage evolves. It is designed to produce high fidelity findings that speed decisions, not alert fatigue.

Common MCP server vulnerabilities include secret exposure, insecure token handling, and weak authorization boundaries. Scope creep is another frequent risk because MCP servers often gain capabilities quickly as teams iterate. Tool poisoning is a growing concern, where compromised plugins or dependencies return manipulated output that steers unsafe actions. Command injection and unsafe execution paths matter because MCP servers can generate actions dynamically. Prompt and context injection matter because attacks can be subtle and workflow dependent. Levo tests across these risk categories and maps coverage to a structured MCP focused taxonomy. This helps teams find the issues that matter before MCP becomes a production execution layer.

Authentication testing should validate that tool calls cannot be invoked without valid credentials and that failure behavior is safe. Authorization testing should validate that identities cannot do more than intended, even when requests look legitimate. This testing should include denied path validation, replay attempts, and wrong identity states, not only successful calls. The goal is consistent enforcement across chained tool calls, because MCP workflows often cross multiple systems in one sequence. Levo executes tests under realistic access conditions and validates boundary behavior, so teams can expand MCP usage without expanding privilege silently. This helps approvals move faster because controls can be demonstrated, not assumed.

Prompt injection testing checks whether malicious instructions can override policy, extract sensitive information, or manipulate tool execution. It matters for MCP because servers translate natural language intent into tool calls, creating a direct path from text to execution. Good testing includes indirect instructions, multi step manipulation, and attempts that persist across context and tool calls. It also validates that safety holds under pressure, when prompts try to coerce the system into doing the risky thing. Levo tests MCP servers with adversarial prompts and workflow shaped manipulation attempts, not just obvious “jailbreak” strings. It is designed to preserve legitimate use while proving execution stays inside defined boundaries.

MCP tool poisoning is when a compromised tool, plugin, or dependency returns manipulated output that steers an agent into unsafe actions. It is dangerous because poisoned outputs can look legitimate, so compromise can propagate quietly through normal workflows. Testing should inject corrupted tool outputs and misleading responses to see whether the server validates what it consumes. It should also test cross-tool chaining, where one poisoned output influences later tool calls and downstream decisions. Levo explicitly tests tool poisoning by simulating compromised tool outputs and edge case payloads. This turns “trusted plugin” assumptions into measurable proof before MCP is scaled.

Secrets exposure testing checks whether tokens, credentials, or sensitive identifiers appear in responses, logs, caches, or error messages. It should validate token lifetimes, storage patterns, and failure behavior so accidental spills do not become persistent access. Data exfiltration testing should include context leakage across sessions and chains, because MCP workflows often persist context across steps. The desired outcome is containment, so sensitive data stays scoped to the right workflow and does not leak into tool outputs or logs. Levo approaches secret exposure like a leak hunt and validates safe failure behavior in realistic runtime conditions. It also tests boundary behavior so context cannot quietly escape into downstream systems.

Point in time testing catches obvious issues before deployment, but MCP risk changes as tools, permissions, and workflows evolve. MCP servers can add tools, expand scopes, or change behavior without clear “release” signals, which makes drift a predictable failure mode. Continuous testing is what keeps governance aligned with real change, not last quarter’s posture. The business outcome is stability: fewer surprises, fewer late stage rewrites, and fewer emergency pauses after an issue is found in production. Levo supports continuous validation so new MCP servers, new tools, and behavior changes do not silently expand risk. It also avoids dependency on teams self reporting inventory, which is where many programs fall behind.

An MCP security testing program should produce evidence of what was tested, what failed, what was remediated, and what passed. It should tie findings to specific servers, tool surfaces, and authentication states, not generic scan results. It should show that common MCP failure modes are covered and that testing aligns to a consistent taxonomy. It should also support repeatable reporting over time, because auditors and risk teams care about drift, not one successful test. Levo’s MCP Security Testing is built to generate audit ready evidence while keeping findings actionable and defensible. This reduces approval friction by anchoring risk decisions in proof rather than debate.