A mannequin context protocol (MCP) software can declare to execute a benign process resembling “validate electronic mail addresses,” but when the software is compromised, it may be redirected to satisfy ulterior motives, resembling exfiltrating your total handle e-book to an exterior server. Conventional safety scanners might flag suspicious community calls or harmful capabilities and pattern-based detection might determine recognized threats, however neither functionality can join a semantic and behavioral mismatch between what a software claims to do (electronic mail validation) and what it truly does (exfiltrate knowledge).
Introducing behavioral code scanning: the place safety evaluation meets AI
Addressing this hole requires rethinking how safety evaluation works. For years, static utility safety testing (SAST) instruments have excelled at discovering patterns, tracing dataflows, and figuring out recognized risk signatures, however they’ve at all times struggled with context. Answering questions like, “Is a community name malicious or anticipated?” and “Is that this file entry a risk or a function?” requires semantic understanding that rule-based methods can’t present. Whereas massive language fashions (LLMs) convey highly effective reasoning capabilities, they lack the precision of formal program evaluation. This implies they’ll miss delicate dataflow paths, battle with complicated management constructions, and hallucinate connections that don’t exist within the code.
The answer is in combining each: rigorous static evaluation capabilities that feed exact proof to LLMs for semantic evaluation. It delivers each the precision to hint precise knowledge paths, in addition to the contextual judgment to guage whether or not these paths characterize reliable habits or hidden threats. We applied this in our behavioral code scanning functionality into our open supply MCP Scanner.
Deep static evaluation armed with an alignment layer
Our behavioral code scanning functionality is grounded in rigorous, language-aware program evaluation. We parse the MCP server code into its structural parts and use interprocedural dataflow evaluation to trace how knowledge strikes throughout capabilities and modules, together with utility code, the place malicious habits typically hides. By treating all software parameters as untrusted, we map their ahead and reverse flows to detect when seemingly benign inputs attain delicate operations like exterior community calls. Cross-file dependency monitoring then builds full name graphs to uncover multi-layer habits chains, surfacing hidden or oblique paths that might allow malicious exercise.
In contrast to conventional SAST, our method makes use of AI to check a software’s documented intent towards its precise habits. After extracting detailed behavioral alerts from the code, the mannequin seems to be for mismatches and flags instances the place operations (resembling community calls or knowledge flows) don’t align with what the documentation claims. As a substitute of merely figuring out harmful capabilities, it asks whether or not the implementation matches its said function, whether or not undocumented behaviors exist, whether or not knowledge flows are undisclosed, and whether or not security-relevant actions are being glossed over. By combining rigorous static evaluation with AI reasoning, we will hint precise knowledge paths and consider whether or not these paths violate the software’s said function.
Bolster your defensive arsenal: what behavioral scanning detects
Our improved MCP Scanner software can seize a number of classes of threats that conventional instruments miss:
- Hidden Operations: Undocumented community calls, file writes, or system instructions that contradict a software’s said function. For instance, a software claiming to help with sending emails that secretly bcc’s all of your emails to an exterior server. This compromise truly occurred, and our behavioral code scanning would have flagged it.
- Knowledge Exfiltration: Instruments that carry out their said perform appropriately whereas silently copying delicate knowledge to exterior endpoints. Whereas the consumer receives the anticipated consequence; an attacker additionally will get a replica of that knowledge.
- Injection Assaults: Unsafe dealing with of consumer enter that allows command injection, code execution, or comparable exploits. This consists of instruments that go parameters straight into shell instructions or evaluators with out correct sanitization.
- Privilege Abuse: Instruments that carry out actions past their said scope by accessing delicate assets, altering system configurations, or performing privileged operations with out disclosure or authorization.
- Deceptive Security Claims: Instruments that assert that they’re “secure,” “sanitized,” or “validated” whereas missing the protections and making a harmful false assurance.
- Cross-boundary Deception: Instruments that seem clear however delegate to helper capabilities the place the malicious habits truly happens. With out interprocedural evaluation, these points would evade surface-level evaluate.
Why this issues for enterprise AI: the risk panorama is ever rising
Should you’re deploying (or planning to deploy) AI brokers in manufacturing, think about the risk panorama to tell your safety technique and agentic deployments:
Belief choices are automated: When an agent selects a software primarily based on its description, that’s a belief resolution made by software program, not a human. If descriptions are deceptive or malicious, brokers could be manipulated.
Blast radius scales with adoption: A compromised MCP software doesn’t have an effect on a single process, it impacts each agent invocation that makes use of it. Relying on the software, this has the potential to influence methods throughout your total group.
Provide chain threat is compounding: Public MCP registries proceed to increase, and growth groups will undertake instruments as simply as they undertake packages, typically with out auditing each implementation.
Guide evaluate processes miss semantic violations: Code evaluate catches apparent points, however distinguishing between reliable and malicious use of capabilities is tough to determine at scale.
Integration and deployment
We designed behavioral code scanning to combine seamlessly into present safety workflows. Whether or not you’re evaluating a single software or scanning a complete listing of MCP servers, the method is easy and the insights are actionable.
CI/CD pipelines: Run scans as a part of your construct pipeline. Severity ranges assist gating choices, and structured outputs permits programmatic integration.
A number of output codecs: Select concise summaries for CI/CD, detailed reviews for safety evaluations, or structured JSON for programmatic consumption.
Black-box and white-box protection: When supply code isn’t obtainable, customers can depend on present engines resembling YARA, LLM-based evaluation, or API scanning. When supply code is accessible, behavioral scanning supplies deeper, evidence-driven evaluation.
Versatile AI ecosystem assist: Suitable with main LLM platforms so you possibly can deploy in alignment together with your safety and compliance necessities
A part of Cisco’s dedication to AI safety
Behavioral code scanning strengthens Cisco’s complete method to AI safety. As a part of the MCP Scanner toolkit, it enhances present capabilities whereas additionally addressing semantic threats that conceal in plain sight. Securing AI brokers requires the assist of instruments which might be purpose-built for the distinctive challenges of agentic methods.
When paired with Cisco AI Protection, organizations achieve end-to-end safety for his or her AI purposes: from provide chain validation and algorithmic crimson teaming to runtime guardrails and steady monitoring. Behavioral code scanning provides a crucial pre-deployment verification layer that catches threats earlier than they attain manufacturing.
Behavioral code scanning is accessible at the moment in MCP Scanner, Cisco’s open supply toolkit for securing MCP servers, giving organizations a sensible to validate the instruments their brokers depend upon.
For extra on Cisco’s complete AI safety method, together with runtime safety and algorithmic crimson teaming, go to cisco.com/ai-defense.

