LLM Security Tools
Tools for securing LLM applications against prompt injection, data leakage, jailbreaking, and compliance violations.
Why LLM Security Tools Matter
Traditional application security (WAFs, SAST, DAST) does not address LLM-specific attack vectors. Prompt injection alone has been classified as the #1 risk in the OWASP Top 10 for LLM Applications.
Key threats LLM security tools address:
- Prompt injection and jailbreak attacks
- PII and sensitive data leakage in prompts and responses
- Harmful or toxic content generation
- Indirect injection via RAG documents
- Excessive token usage (cost attacks)
Tool Comparison Matrix
| Feature | Lakera Guard | Guardrails AI | Rebuff | SlashLLM |
|---|---|---|---|---|
| Primary Focus | Prompt injection defense | Output validation | Multi-layer injection detection | End-to-end AI security platform |
| Architecture | API middleware | Python library wrapper | API + vector DB | Full platform (gateway + SOC) |
| Prompt Injection | ✅ Real-time ML detection | ⚠️ Basic via validators | ✅ Multi-layer detection | ✅ Gateway-level defense |
| Output Validation | ⚠️ Limited | ✅ Full structured validation | ❌ Input-focused | ✅ Guardrails + monitoring |
| PII Protection | ✅ Built-in | ✅ Via validators | ❌ | ✅ Built-in |
| Self-hosted | ✅ Docker/K8s | ✅ Python library | ✅ Self-hosted | ✅ Docker/K8s |
| Open Source | ❌ Proprietary | ✅ Apache 2.0 | ✅ Open-source | ❌ Proprietary |
| Enterprise | ✅ SOC2, SIEM | ⚠️ Developer-focused | ⚠️ Limited | ✅ SOC2, ISO 27001, HIPAA |
| Pricing | Free tier + Enterprise | Free (OSS) + Enterprise | Free (OSS) | Flat-rate tiers |
Lakera Guard
Real-time LLM security and prompt injection defense.
Lakera Guard deploys as a middleware layer between your application and the LLM provider. It uses ML-based detection to identify prompt injection, data leakage, and harmful content in real-time.
Architecture
Application → Lakera Guard API → LLM Provider
│
┌─────┴──────┐
│ Detection │
│ Engine │
├─────────────┤
│ • Prompt │
│ injection │
│ • PII scan │
│ • Toxicity │
│ • Jailbreak │
└─────────────┘
Use Cases
- Real-time prompt injection detection before LLM inference
- PII and data leakage prevention in prompts and responses
- Content moderation for customer-facing LLM applications
- Compliance enforcement for regulated industries
When to Choose Lakera Guard
Choose Lakera Guard when you need infrastructure-level prompt injection defense without modifying application code. Best for security teams in regulated industries.
→ Full Lakera Guard Review · Lakera Guard vs Guardrails AI
Guardrails AI
Input/output validation framework for LLM applications.
Guardrails AI wraps LLM calls with validators that enforce structure, detect toxicity, check factuality, and apply custom business rules. Open-source with a community Validator Hub.
Architecture
Application Code
│
▼
┌──────────────────┐
│ Guard Wrapper │
│ ┌────────────┐ │
│ │ Validators │ │
│ │ (pre/post) │ │
│ └─────┬──────┘ │
│ ▼ │
│ LLM API Call │
│ ▼ │
│ ┌────────────┐ │
│ │ Output │ │
│ │ Validation │ │
│ └────────────┘ │
└──────────────────┘
Use Cases
- Output format validation (enforce JSON, XML schemas)
- Toxicity and bias filtering before user delivery
- Factuality checking against reference sources
- Custom business rule enforcement per use case
When to Choose Guardrails AI
Choose Guardrails AI when you need fine-grained control over LLM outputs within your application code. Best for developers building production applications who need output quality guarantees.
→ Lakera Guard vs Guardrails AI
Rebuff
Self-hardening prompt injection detection.
Rebuff uses a multi-layer approach — heuristics, LLM-based analysis, and a vector database of known attacks — to detect and learn from prompt injection attempts.
Architecture
User Input
│
▼
┌──────────────────────┐
│ Layer 1: Heuristics │ ← Pattern matching
├──────────────────────┤
│ Layer 2: LLM Judge │ ← AI-based analysis
├──────────────────────┤
│ Layer 3: Vector DB │ ← Known attack patterns
└──────────────────────┘
│
▼
Score → Allow / Block
Use Cases
- Multi-layer prompt injection defense with learning capability
- Attack pattern collection for continuous improvement
- API gateway integration for centralized protection
- Red team testing and attack simulation
When to Choose Rebuff
Choose Rebuff when you want an open-source, self-improving detection system that learns from attacks. Good for teams building custom security pipelines.
SlashLLM
Integrated Service Provider for AI Security — platform, operations, and governance.
SlashLLM sits between your applications and any LLM provider, combining API gateway, guardrails, observability, red-teaming, and governance into one managed platform with 24/7 AI-SOC monitoring.
Architecture
Applications → SlashLLM Platform → LLM Providers
│
┌──────────┴──────────┐
│ │
┌─────▼──────┐ ┌──────▼──────┐
│ Gateway + │ │ AI-SOC │
│ Guardrails │ │ Monitoring │
├────────────┤ ├─────────────┤
│ Rate limit │ │ 24/7 alerts │
│ PII filter │ │ Compliance │
│ Injection │ │ Red-teaming │
│ defense │ │ Audit logs │
└────────────┘ └─────────────┘
Use Cases
- End-to-end LLM security without building your own stack
- 24/7 AI-SOC monitoring for prompt injection and data exfiltration
- Automated compliance evidence (SOC 2, ISO 27001, HIPAA, GDPR, EU AI Act)
- CI/CD-integrated red-teaming and jailbreak testing
When to Choose SlashLLM
Choose SlashLLM when you need an all-in-one managed security platform with SOC monitoring. Best for enterprises that want comprehensive coverage without assembling multiple tools.
Implementation Guidance
Recommended Stack by Team Size
| Team Size | Recommendation |
|---|---|
| Startup (< 10 eng) | Guardrails AI for output validation + basic rate limiting |
| Growth (10-50 eng) | Lakera Guard for injection defense + Guardrails AI for output quality |
| Enterprise (50+ eng) | SlashLLM or Lakera Guard enterprise + Guardrails AI + custom policies |