ECLIPSE: Self-Evolving Stealthy Prompt Injection Attack against Long-Horizon Agentic Systems
long-horizon tasks through repeated tool calls. This capability also creates new opportunities for prompt injection. Existing attacks either place the malicious objective in one explicit instruction, making it easy
AI Agents May Always Fall for Prompt Injections
Prompt injection is the most critical vulnerability in deployed AI agents. Despite recent progress, we show that the prevailing defense paradigm (data-instruction separation) both fails to detect attacks that
AgentAntibody: An Adaptive Immune System for Defending LLM Agents against Prompt Injection
Prompt injection remains a critical threat to LLM agents, yet existing defenses treat each task as a self-contained problem, independent of previous encounters. In practice, user requests are often
DeepSeek Robustness Against Semantic-Character Dual-Space Mutated Prompt Injection
Prompt injection has emerged as a critical security threat to large language models (LLMs), yet existing studies predominantly focus on single-dimensional attack strategies, such as semantic rewriting or character
SEAL: Sealed Queries for Local Sanitization against Indirect Prompt Injection
Indirect prompt injection threatens local LLM agents through untrusted tool outputs, motivating defenses that suppress attacks while preserving task evidence under limited inference budgets. We introduce SEAL, which learns
Attention-based Classification for Indirect Prompt Injection
Indirect prompt injection (IPI) attacks, in which adversarial instructions are embedded in external data processed by a language model, pose a significant threat to the integrity of deployed LLM agents
DRIP: Defending Prompt Injection via Token-wise Representation Editing and Residual Instruction Fusion
they process user data according to predefined instructions. However, conventional LLMs remain vulnerable to prompt injection, where malicious users inject directive tokens into the data to subvert model behavior. Existing
From Detection to Decision: Calibration and Deferral for Prompt-Injection Detection
Llama Prompt Guard 2 classifiers (22M and 86M), and an LLM-based judge on 47,611 held-out examples spanning direct and indirect prompt injections, hard-benign inputs, obfuscation
Can CaMeLs Talk? Securing Multi-Agent Systems Against Indirect Prompt Injection Attacks
Indirect prompt injection attacks - malicious instructions embedded in content processed by large language models - remain a major obstacle to safely deploying tool-using agents. CaMeL [Debenedetti et al., 2025] mitigates
Multilingual Hidden Prompt Injection Attacks on LLM-Based Academic Reviewing
find that prompt injection induces substantial changes in review scores and accept/reject decisions for English, Japanese, and Chinese injections, while Arabic injections produce little to no effect. These results highlight
Heads of Security: Learned Attention Gates Improve Prompt Injection Robustness
introduce Heads of Security (HoS), a prompt injection defense that enforces instruction-data separation via a small set of learned per-head attention gates. HoS learns how each head should
Semantics as a Shield: Label Disguise Defense (LDD) against Prompt Injection in LLM Sentiment Classification
classification tasks such as sentiment analysis, yet their reliance on natural language prompts exposes them to prompt injection attacks. In particular, class-directive injections exploit knowledge of the model
WebSentinel: Detecting and Localizing Prompt Injection Attacks for Web Agents
Prompt injection attacks manipulate webpage content to cause web agents to execute attacker-specified tasks instead of the user's intended ones. Existing methods for detecting and localizing such attacks
Climbing the Hill: Prompt Injection Red-Teaming Against Frontier Models with Curriculum Reinforcement Learning
teaming methods for prompt injection leverage reinforcement learning (RL) to train an attacker LLM to generate effective injected prompts. However, when targeting frontier LLMs such as GPT-6-Luna
ObliInjection: Order-Oblivious Prompt Injection Attack to LLM Agents with Multi-source Data
Prompt injection attacks aim to contaminate the input data of an LLM to mislead it into completing an attacker-chosen task instead of the intended task. In many applications
Same Bytes, Different Authority: Reserved-Token Representations in Chat-Template Prompt Injection
Prompt injection against LLM agents becomes much stronger when the injected instruction is wrapped in the model's own chat template. A forged template marker such as <|im_start
Prompt Injection in Automated Résumé Screening with Large Language Models: Single and Multi-Injection Settings
homogeneous and few candidates inject. However, its effectiveness rapidly diminishes as more candidates inject, collapsing when manipulation becomes widespread. When candidate quality is heterogeneous, prompt injection is less effective
Defending Against Prompt Injection with DataFilter
agents are increasingly deployed to automate tasks and interact with untrusted external data, prompt injection emerges as a significant security threat. By injecting malicious instructions into the data that LLMs
A Layered Security Framework Against Prompt Injection in RAG-Based Chatbots
Prompt injection is ranked as the most critical vulnerability in large language model (LLM) deployments by the OWASP Top 10 for LLM Applications, yet existing defenses operate at isolated pipeline
PIDS-Bench: Evaluating Prompt-Injection Detectors Under Over-Defense, Obfuscation, and Distribution Shift
Prompt-injection detectors are typically evaluated using aggregate F1 on in-distribution test data, which offers limited insight into behavior under distribution shift, particularly on the benign side