Prompt Injection Vulnerability Checker
Analyze your chatbot's system prompt against 31 injection attack patterns. Get a security score, identify vulnerabilities, and get specific fix suggestions.
Paste Your System Prompt
How LochBot Works
LochBot is a free prompt injection vulnerability checker that analyzes your chatbot's system prompt for security weaknesses. The tool tests your prompt text against 31 known injection attack patterns organized across 7 categories: direct injection, context manipulation, delimiter attacks, data extraction, role play jailbreaks, encoding attacks, and prompt leaking. Each attack pattern has been documented in security research from organizations like OWASP and validated against real-world prompt injection attempts.
When you paste your system prompt and click "Analyze," LochBot performs client-side pattern matching to check whether your prompt contains defensive language against each attack vector. The tool looks for specific defensive phrases, structural elements like XML delimiters, immutability declarations, and refusal examples. Each vulnerability is scored by severity — critical, high, medium, or low — and the results are aggregated into a 0-100 security score with a letter grade from A through F. For every failed test, LochBot provides a specific fix suggestion you can add directly to your system prompt.
Features
LochBot provides instant security scoring with a comprehensive breakdown by attack category. The tool generates specific fix suggestions for each detected vulnerability, making it actionable rather than just diagnostic. Results can be exported as JSON for documentation, compliance reporting, or integration into your development workflow. The analysis covers the full spectrum of prompt injection techniques from simple instruction overrides to sophisticated encoding-based attacks. For teams building AI-powered chatbots, LochBot pairs well with ClaudHQ for Claude API management and InvokeBot for testing webhook integrations in your chatbot infrastructure.
Who Uses This
LochBot is used by security engineers auditing chatbot deployments, developers building LLM-powered applications, and product teams launching customer-facing AI features. Common use cases include pre-deployment security reviews of system prompts, comparing the security posture of different prompt designs, and training team members on prompt injection defense techniques. Organizations in regulated industries use LochBot to document their prompt security assessment as part of compliance requirements. The tool is also used by AI security researchers studying the effectiveness of different defensive patterns against prompt injection attacks.
Privacy
LochBot runs entirely in your browser. Your system prompt never leaves your machine. All analysis is done using local JavaScript pattern matching and heuristics — there are no API calls, no server-side processing, no analytics tracking your prompt content, and no data storage. The source code is available on GitHub for inspection. You can verify the client-side-only behavior by checking your browser's network tab during analysis.
Frequently Asked Questions
What is prompt injection?
Prompt injection is a security vulnerability where an attacker crafts input that manipulates an AI chatbot into ignoring its system prompt instructions. Attacks include direct instruction overrides, role play jailbreaks, and data extraction attempts. It is the number one security risk for LLM-powered applications according to the OWASP Top 10 for LLMs.
How do I test my chatbot for prompt injection?
Paste your chatbot's system prompt into LochBot. The prompt injection checker analyzes your prompt against 31 attack types across 7 categories. You get a 0-100 security score, letter grade, and specific fix suggestions for each vulnerability detected.
What are the most common prompt injection attacks?
The most common attacks are direct instruction override, system prompt extraction, DAN jailbreaks, delimiter escape attacks, and context manipulation. These five prompt injection patterns cover roughly 80% of injection attempts seen in the wild.
How do I make my system prompt more secure?
Use unique XML delimiters, explicitly forbid instruction disclosure with multiple verb variants, block role changes by name, include few-shot refusal examples, and declare your instructions as immutable. LochBot tests for all of these defensive patterns.
Does this tool send my data anywhere?
No. LochBot is 100% client-side. Your system prompt never leaves your browser. All analysis runs using local pattern matching in JavaScript with no API calls, no server processing, and no data collection.
What is the difference between LochBot and red-team testing?
LochBot analyzes your prompt's defensive structure using pattern matching. Red-team testing sends actual attack inputs to your deployed model to see if it resists them. LochBot is a first-pass structural analysis; red-team testing is a behavioral test against a running model. Both are needed for comprehensive prompt security.
Can I export the vulnerability report?
Yes. After analyzing your system prompt, click the Export JSON button to download a complete vulnerability report. The export includes your security score, grade, and detailed results for each of the 31 attack patterns tested.