owasp-llm-top10
Security audit for LLM and GenAI applications using OWASP Top 10 for LLM Apps 2025. Assess prompt injection, data leakage, supply chain, and 7 more critical vulnerabilities.
By mastepanoski · 375 installs
npx skills add mastepanoski/claude-skills --skill owasp-llm-top10
Source repository · Upstream listing
OWASP Top 10 for LLM Applications Security Audit
This skill enables AI agents to perform a comprehensive security assessment of Large Language Model (LLM) and Generative AI applications using the OWASP Top 10 for LLM Applications 2025 , published by the OWASP GenAI Security Project.
The OWASP Top 10 for LLM Applications identifies the most critical security risks in systems that integrate large language models, covering vulnerabilities from prompt injection to unbounded resource consumption. This is the authoritative industry standard for LLM application security.
Use this skill to identify security vulnerabilities, assess risk exposure, prioritize remediation, and establish secure development practices for AI powered applications.
Combine with "NIST AI RMF" for comprehensive risk management or "ISO 42001 AI Governance" for governance compliance.
When to Use This Skill
Invoke this skill when:
Auditing security of LLM powered applications before deployment
Reviewing GenAI integrations for security vulnerabilities
Assessing RAG (Retrieval Augmented Generation) systems
Evaluating chatbot or AI assistant security
Conducting penetration testing of AI features
Building secure AI application architectures
Reviewing third party AI API integrations
Preparing for security compliance reviews
Responding to AI related security incidents
Inputs Required
When executing this audit, gather:
application description : Description of the AI application (purpose, LLM used, architecture, features, user base) [REQUIRED]
architecture details : System architecture (APIs, databases, vector stores, plugins, integrations) [OPTIONAL but recommended]
llm provider : LLM provider and model (OpenAI GPT 4, Anthropic Claude, self hosted, etc.) [OPTIONAL]
deployment context : Deployment environment (cloud, on premise, hybrid, edge) [OPTIONAL]
data sensitivity : Types of data processed (PII, financial, health, proprietary) [OPTIONAL]
existing controls : Current security measures (auth, rate limiting, content filtering) [OPTIONAL]
specific concerns : Known vulnerabilities or areas of focus [OPTIONAL]
testing authorization : Explicit authorization, environment, and boundaries for active testing [REQUIRED for live or active tests]
safe testing mode : documentation only, staging, production readonly, or production approved [OPTIONAL, defaults to documentation only unless authorization is clear]
Authorized Testing Boundary
Only run active security tests on systems the user owns or is explicitly authorized to test. If authorization is absent or unclear, perform a documentation and architecture review only, using safe hypothetical examples instead of live payload execution.
For production systems:
Prefer staging or read only validation
Avoid denial of service, destructive, persistence, or real exfiltration tests unless written scope explicitly permits them
Redact credentials, secrets, PII, and sensitive prompt or model outputs in reports
Stop and report if testing crosses the approved scope
The OWASP Top 10 for LLM Applications (2025)
Per vulnerability description, attack scenarios, detection checks, and mitigations are in
[ references/llm vulnerabilities.md ](references/llm vulnerabilities.md) . Read the entries relevant to the application's architecture.
ID Vulnerability
LLM01 Prompt Injection
LLM02 Sensitive Information Disclosure
LLM03 Supply Chain Vulnerabilities
LLM04 Data and Model Poisoning
LLM05 Improper Output Handling
LLM06 Excessive Agency
LLM07 System Prompt Leakage
LLM08 Vector and Embedding Weaknesses
LLM09 Misinformation
LLM10 Unbounded Consumption
Audit Procedure
Step 1: Application Understanding (15 minutes)
1. System inventory:
Document LLM provider, model version, and configuration
Map application architecture (APIs, databases, vector stores)
Identify all data flows to and from the LLM
List plugins, tools, and integrations
2. Threat modeling:
Identify attack surfaces (user inputs, APIs, data sources)
Determine data sensitivity classification
Map trust boundaries between components
Identify privileged operations the LLM can trigger
Step 2: Vulnerability Assessment (40 60 minutes)
For each of the 10 vulnerabilities, assess:
Prompt Injection (LLM01) 10 min
[ ] Test with known injection techniques (direct and indirect)
[ ] Attempt to override system instructions
[ ] Test with malicious content in external data sources
[ ] Verify input validation and sanitization
Sensitive Information Disclosure (LLM02) 5 min
[ ] Attempt to extract training data
[ ] Test for PII leakage in outputs
[ ] Check for credential or API key exposure
[ ] Verify output filtering effectiveness
Supply Chain (LLM03) 5 min
[ ] Review model provenance and source
[ ] Check dependency versions and vulnerability status
[ ] Verify plugin and integration security
[ ] Review SBOM completeness
Data/Model Poisoning (LLM04) 5 min
[ ] Review data pipeline security
[ ] Check fine tuning data validation
[ ] Verify model integrity monitoring
[ ] Test with known trigger patterns
Improper Output Handling (LLM05) 10 min
[ ] Test for XSS through LLM outputs
[ ] Attempt SQL injection via model responses
[ ] Check command injection possibilities
[ ] Verify output sanitization and encoding
Excessive Agency (LLM06) 5 min
[ ] Review agent permissions and capabilities
[ ] Test privilege boundaries
[ ] Verify human in the loop for critical actions
[ ] Check audit logging completeness
System Prompt Leakage (LLM07) 5 min
[ ] Attempt to extract system prompts
[ ] Check for secrets in prompts
[ ] Verify prompt protection mechanisms
Vector/Embedding Weaknesses (LLM08) 5 min
[ ] Review vector store access controls
[ ] Test RAG retrieval for injection
[ ] Verify data separation and filtering
Misinformation (LLM09) 5 min
[ ] Test for hallucination in critical domains
[ ] Verify grounding and citation mechanisms
[ ] Check confidence indicators
Unbounded Consumption (LLM10) 5 min
[ ] Test rate limiting effectiveness
[ ] Verify token and cost limits
[ ] Check timeout configurations
Step 3: Risk Scoring (15 minutes)
For each vulnerability found, score using:
Likelihood : How likely is exploitation?
High : Known attack vectors, easy to exploit, publicly accessible
Medium : Requires some skill or specific conditions
Low : Difficult to exploit, limited attack surface
Impact : What is the potential damage?
Critical : System compromise, major data breach, significant financial loss
High : Unauthorized access, data exposure, service disruption
Medium : Limited data exposure, partial service impact
Low : Minor information disclosure, minimal impact
Step 4: Report Generation (20 minutes)
Compile comprehensive security assessment.
Output Format
The copy ready audit report template (executive summary, findings per vulnerability, risk scoring,
remediation plan) is in [ references/report template.md ](references/report template.md) .
Quick Reference: Vulnerability Priority
Priority Vulnerabilities Rationale
P0 LLM01 (Prompt Injection), LLM02 (Data Disclosure) Direct exploitation, high impact
P1 LLM05 (Output Handling), LLM06 (Excessive Agency) System compromise potential
P2 LLM03 (Supply Chain), LLM04 (Poisoning) Harder to exploit but severe impact
P3 LLM07 (Prompt Leakage), LLM08 (Vector Weaknesses) Enables further attacks
P4 LLM09 (Misinformation), LLM10 (Unbounded Consumption) Operational risk
Best Practices
1. Defense in depth : Never rely on a single security control
2. Zero trust for LLM output : Treat all model output as untrusted
3. Least privilege : Minimize AI agent permissions and capabilities
4. Monitor continuously : Log and alert on anomalous AI behavior
5. Test adversarially : Regular red team exercises against AI features
6. Secure the pipeline : Protect training data, models, and embeddings
7. Human oversight : Maintain human in the loop for critical operations
8. Update regularly : Stay current with evolving attack techniques
9. Educate users : Train users on safe AI interaction practices
10. Plan for incidents : Have AI specific incident response procedures
Version
1.0 Initial release (OWASP Top 10 for LLM Applications 2025)
Remember : LLM security is an evolving field. New attack vectors emerge regularly. This audit provides a baseline assessment; continuous monitoring and periodic re assessment are essential for maintaining security posture.