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No single product can secure an AI application against prompt injection or data leakage. The workable approach is layered: limit what the model and its tools can reach, treat everything the model reads as potentially hostile, and add runtime guardrails that inspect prompts, retrieved content, tool calls and responses. The nine products below are a shortlist to evaluate, not a ranking.
How to read this shortlist
None of the nine products is placed above another, and this article does not report a head-to-head performance test. Evidence for three products comes from vendor documentation that describes intended capabilities. The other six appear only in OWASP’s 2026 solutions landscape, a guide that helps identify vendors in the space but does not establish how well any of them perform. Vendor documentation is useful for understanding what a product is designed to do; it is not independent proof that the product stops a given attack.
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Where prompt injection and data leakage come from
OWASP treats prompt injection as a current top risk for LLM applications. Its official Top 10 page states the consequence directly: “Manipulating LLMs via crafted inputs can lead to unauthorized access, data breaches, and compromised decision-making.”
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A free scan shows the junk files, broken settings and background clutter dragging Windows down - then fixes them in one click.Free scan · Windows 10 & 11The attack arrives through several channels, and each one needs a different kind of attention. Direct injection comes from what a user types. Indirect injection comes from content the application fetches on the user’s behalf. Agents add further channels, because tool responses and tool descriptions are also passed to the model.
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- POWERFUL SECURITY KEY: The Security Key C NFC is the essential physical passkey for protecting your digital life from phishing attacks. It ensures only you can access your accounts.
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| Entry point | Example | What it can lead to |
|---|---|---|
| Direct user input | A chat message telling the model to ignore its instructions | Unauthorized actions or disclosure of protected content |
| Retrieved content | A web page, PDF, email or database record containing hidden instructions | The model acting on text it was only meant to summarize |
| Tool responses and descriptions | An API result or tool metadata carrying instructions | An agent taking actions the user never requested |
| Model output and system prompt | A response that repeats internal instructions or personal data | Sensitive data reaching the user, logs or downstream systems |
| Connected actions | An agent with write access to email, files or payments | Unauthorized access, data breaches or harmful decisions |
Data leakage is therefore not only a detection problem. Sensitive information can surface in model output, and system-prompt leakage is one well-known form of it. How much data the model can see in the first place is a design decision that no filter fully corrects.
Controls to put in place before choosing a product
A guardrail is most useful as one layer in a design that already limits the damage when something gets through.
Rank #2
- POWERFUL SECURITY KEY: The YubiKey 5C NFC is the most versatile physical passkey, protecting your digital life from phishing attacks. It ensures only you can access your accounts
- WORKS WITH 1000+ ACCOUNTS: Compatible with popular accounts like Google, Microsoft, and Apple. A single YubiKey 5C NFC secures 100+ of your favorite accounts, including email, password managers, and more
- FAST & CONVENIENT LOGIN: Plug in your YubiKey 5C NFC via USB and tap it, or tap it against your phone (NFC), to authenticate. No batteries, no internet connection, and no extra fees required
- MOST SECURE PASSKEY: Supports FIDO2/WebAuthn, FIDO U2F, Yubico OTP, OATH-TOTP/HOTP, Smart card (PIV), and OpenPGP. That means it’s versatile, working almost anywhere you need it
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- Restrict data and tool access. Give the model only the records and tools a task requires, and scope each credential to that task.
- Treat retrieved content and tool outputs as untrusted. Text from a web page, a file or an API can carry instructions just as user input can.
- Validate inputs and outputs. Check what goes into the model and what comes back against the format and content the application expects.
- Require human approval for sensitive operations. Payments, data exports, permission changes and deletions should not run on model output alone.
- Add runtime guardrails as the next layer. Detection and redaction at the request and response boundary catch a class of problems that the controls above may miss.
- Test adversarially. Attack your own system before users or attackers do, and repeat the tests after every change.
The nine-product shortlist
The table lists the products in the order they are discussed below. The order does not indicate quality.
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|---|---|---|
| Check Point AI Guardrails | Runtime guard API covering agent workflow interactions | Vendor documentation of runtime prompt-attack and data-leakage detection |
| NVIDIA NeMo Guardrails | Developer library, with a production-ready microservice option | Vendor documentation of configurable rails |
| Palo Alto Prisma AIRS AI Gateway guardrails | Inline checks in an AI gateway on requests and responses | Vendor documentation of gateway enforcement actions |
| Lakera | Not stated | Named in OWASP’s 2026 solutions landscape only |
| Cisco AI Validation | Not stated | Named in OWASP’s 2026 solutions landscape only |
| Protect AI | Not stated | Named in OWASP’s 2026 solutions landscape only |
| CalypsoAI | Not stated | Named in OWASP’s 2026 solutions landscape only |
| HiddenLayer | Not stated | Named in OWASP’s 2026 solutions landscape only |
| Straiker | Not stated | Named in OWASP’s 2026 solutions landscape only |
Check Point AI Guardrails
Check Point documents runtime detection for prompt attacks and data leakage. Its coverage extends beyond the user’s message to agent interactions: tool calls, tool responses and tool descriptions. For agents, those channels often carry more risk than the chat box does. Check the current documentation for the enforcement actions available and how policies are configured, since this article does not describe either.
Rank #3
- POWERFUL SECURITY KEY: The YubiKey 5 NFC is the most versatile physical passkey, protecting your digital life from phishing attacks. It ensures only you can access your accounts
- WORKS WITH 1000+ ACCOUNTS: Compatible with popular accounts like Google, Microsoft, and Apple. A single YubiKey 5 NFC secures 100+ of your favorite accounts, including email, password managers, and more
- FAST & CONVENIENT LOGIN: Plug in your YubiKey 5 NFC via USB and tap it, or tap it against your phone (NFC), to authenticate. No batteries, no internet connection, and no extra fees required
- MOST SECURE PASSKEY: Supports FIDO2/WebAuthn, FIDO U2F, Yubico OTP, OATH-TOTP/HOTP, Smart card (PIV), and OpenPGP. That means it’s versatile, working almost anywhere you need it
- PRIMARY & SPARE KEYS: Just like having a spare house key, we recommend buying two YubiKeys - one for daily use and one as a spare. That way you’ll never get locked out of your accounts
NVIDIA NeMo Guardrails
NeMo Guardrails is a developer library for building programmable rails around an LLM application. NVIDIA’s documentation describes rails for jailbreak protection, PII detection, agentic security, and validation of tool calls and results. A production-ready microservice option is also documented. Because capabilities depend on the configuration and on the models or services you connect, two deployments of the same library can behave differently. It suits teams with the engineering capacity to write and maintain their own rails, which is a different proposition from a gateway that sits in front of every model call.
Palo Alto Prisma AIRS AI Gateway guardrails
Prisma AIRS AI Gateway guardrails run inline and check both requests and responses for prompt injection and sensitive data. Each finding can be handled by one of three actions: deny, redact, or log and allow. Regional availability and activation requirements are set out in Palo Alto Networks’ documentation, and they are not summarized here, so confirm them for your deployment before planning around them.
Rank #4
- POWERFUL SECURITY KEY: The Security Key NFC is the essential physical passkey for protecting your digital life from phishing attacks. It ensures only you can access your accounts.
- WORKS WITH 1000+ ACCOUNTS: Compatible with Google, Microsoft, and Apple. A single Security Key NFC secures 100 of your favorite accounts, including email, password managers, and more.
- FAST & CONVENIENT LOGIN: Plug in your Security Key NFC via USB-A and tap it, or tap it against your phone (NFC) to authenticate. No batteries, no internet connection, and no extra fees required.
- TRUSTED PASSKEY TECHNOLOGY: Uses the latest passkey standards (FIDO2/WebAuthn & FIDO U2F) but does not support One-Time Passwords. For complex needs, check out the YubiKey 5 Series.
- BUILT TO LAST: Made from tough, waterproof, and crush-resistant materials. Manufactured in Sweden and programmed in the USA with the highest security standards.
The six vendors named in OWASP’s landscape
OWASP’s 2026 solutions landscape names six further vendors. Their presence here reflects that listing alone. This article does not describe their features, deployment options or availability, so do not assume any capability from the name. Check each vendor’s current product documentation against the criteria in the next section.
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- Cisco AI Validation
- Protect AI
- CalypsoAI
- HiddenLayer
- Straiker
How to compare options against your architecture
Compare the tools against your own architecture rather than against each other’s marketing. Five questions separate them:
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- Where it sits. Is it a library you embed, an API you call, an inline gateway or a managed service? Map which points in your flow it sees: user prompt, retrieval, model response, tool call and tool result.
- What it covers. Confirm direct and indirect prompt injection, retrieved content, tool descriptions and responses, jailbreaks, PII and output disclosure as separate items. Broad “AI security” positioning does not prove coverage of each category.
- What it can do. Can it block, redact, flag or only log? Find out which actions apply to which finding types, and whether policies can differ between applications.
- What sits behind it. Detection reduces exposure but does not define what the model can reach. Pair any tool with least-privilege access and human review of high-impact actions.
- How strong the evidence is. Separate vendor feature descriptions from independent evaluations and from your own test results. Only your own testing shows how a tool behaves on your traffic.
How to test a guardrail before relying on it
Run these checks against a staging copy of the application using synthetic data, never real customer records.
Quick Recap
- Build a set of direct injection prompts, including role-play and instruction-override variants.
- Place hostile instructions inside a document the retriever will return, and check whether the model follows them.
- Add instructions to a tool response and to a tool description, then confirm the guardrail inspects them before the model acts on them.
- Seed fictitious sensitive values, such as a made-up card number, an API-key-shaped string and a fake personal identifier, into data the model can access. Check whether they appear in responses, logs or downstream calls.
- Ask the application to reveal its system prompt and confirm that it refuses.
- Set each enforcement mode you plan to use and confirm the result. A finding handled by log and allow should be recorded without the request being stopped.
- Run ordinary, benign traffic through the same setup and count false positives. Over-blocking breaks legitimate workflows, so a configuration that looks secure may be unusable.
- Repeat the full set after every model, prompt, retriever or tool change.
Failure modes to plan for
- Checking only the chat message. If the guardrail inspects user input alone, instructions in retrieved pages, emails or tool outputs pass through unexamined.
- Log-and-allow left on in production. A finding recorded under that action is evidence after the fact, not a block.
- Redaction that breaks the workflow. Stripping a field a downstream tool needs can cause errors, and teams often respond by disabling the rule.
- Over-permissioned agents. A detected injection still does damage if the agent holds broad credentials and can act without approval.
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