Top 10 prompt injection attacks
Every security team deploying AI should understand these attack techniques. From basic instruction overrides to sophisticated adversarial suffixes — here are the 10 most dangerous prompt injection attacks and how to defend against them.
01
Direct Instruction Override
Explicitly instruct the model to ignore its system prompt and follow attacker instructions.
Detection: ML classifier + known pattern matching
02
Context Switching
Establish a new context ("You are now...") to override existing system instructions.
Detection: Role-change pattern detection
03
Encoded Payloads
Base64, ROT13, hex, or Unicode encoding to bypass text-based filters.
Detection: Multi-encoding decoder + pattern scan
04
Indirect via RAG
Malicious instructions hidden in retrieved documents that execute within LLM context.
Detection: Retrieved content inspection
05
Multi-Turn Escalation
Gradually escalate requests across conversation turns to bypass single-turn detection.
Detection: Conversation-level analysis
06
Jailbreak Prompts
"DAN", "Developer Mode", or hypothetical scenarios to bypass safety alignment.
Detection: Jailbreak pattern database + ML
07
System Prompt Extraction
Trick the model into revealing its system prompt, enabling targeted attacks.
Detection: Output scanning for system prompt content
08
Delimiter Injection
Exploit delimiter handling (```system```, XML tags) to inject system-level instructions.
Detection: Structural analysis + delimiter scanning
09
Payload Splitting
Split injection across multiple inputs or variables that combine at execution.
Detection: Multi-input correlation
10
Adversarial Suffixes
Append computed adversarial tokens that shift model behavior without readable text.
Detection: Token-level anomaly detection
Defense-in-depth approach
No single detection method catches all 10 attack types. PromptWall's prompt firewall uses four complementary layers: ML classification (trained on adversarial datasets), pattern matching (known attack signatures), semantic analysis (intent detection), and structural analysis (delimiter and encoding anomalies). See our detailed injection examples for technical deep-dives.
Defend against all 10 techniques
Deploy multi-layer prompt injection detection with PromptWall.
Frequently asked questions
What is the most dangerous type of prompt injection?+
Indirect injection through RAG or external data sources is considered most dangerous because the user does not initiate the attack — malicious instructions are embedded in retrieved documents and execute silently within the LLM context.
Can prompt injection be fully prevented?+
No single technique provides 100% prevention. Effective defense requires defense-in-depth: ML classification, pattern matching, semantic analysis, and output validation. PromptWall combines multiple detection layers to achieve high detection rates while minimizing false positives.
How do new injection techniques emerge?+
Researchers and attackers continuously discover novel encoding, context-switching, and obfuscation techniques that bypass existing defenses. This is why static rule-based detection is insufficient — ML models must be continuously retrained against emerging attack patterns.