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Last analyzed Sep 9, 2026

Language Model Security Database

985 research findings · 1119 evaluated models

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47 entries

Matches every word across titles, descriptions, sources, affected systems, and models.

Agent Confused Deputy Escalation

Published Analyzed Source: arXiv

Multi-Agent Systems (MAS) orchestrated by Large Language Models (LLMs) are vulnerable to a Confused Deputy privilege escalation attack. This vulnerability arises when an untrusted or low-privilege agent exploits the inter-agent communication channel (e.g., broadcast or peer-to-peer messaging) to manipulate a high-privilege trusted agent into executing sensitive tools on its behalf. The root cause is the lack of mandatory access control policies governing agent-to-agent interactions; trusted…

Taming Various Privilege Escalation in LLM-Based Agent Systems: A Mandatory Access Control Framework
Evaluated models: o1

Agent Persistent Memory Poisoning

Published Analyzed Source: arXiv

Unauthenticated, query-only memory poisoning (Memory Injection Attack - MINJA) in LLM agents equipped with persistent, shared memory allows attackers to manipulate the agent's long-term knowledge base. Adversaries embed malicious "indication prompts" and utilize progressive shortening within seemingly benign queries to induce the agent into autonomously generating and storing corrupted relational mappings. Because the memory is shared and retrieved via similarity (e.g., Levenshtein distance)…

Memory Poisoning Attack and Defense on Memory Based LLM-Agents
Evaluated models: GPT-4o Mini, Gemini 2.0 Flash, Llama 3.1 8B Instruct

CoT Detector Obfuscation Bypass

Published Analyzed Source: arXiv

LLM-based code agents and vulnerability detectors employing Chain-of-Thought (CoT) reasoning are susceptible to automated adversarial code obfuscation. The vulnerability exists because CoT mechanisms expose the model's decision logic, allowing reinforcement learning frameworks (such as CoTDeceptor) to iteratively refine code transformations based on the detector's own reasoning traces. By optimizing for "reasoning instability" and "hallucination" rather than just syntactic evasion, attackers…

CoTDeceptor: Adversarial Code Obfuscation Against CoT-Enhanced LLM Code Agents
Evaluated models: DeepSeek R1, GPT-5

Grafted Experience Drift

Published Analyzed Source: arXiv

A vulnerability exists in MetaGPT's DataInterpreter agent (and similar RAG-based agents utilizing persistent long-term memory) that allows for persistent memory poisoning via indirect injection. The vulnerability exploits the agent's "semantic imitation heuristic," where the agent blindly trusts and imitates retrieved past experiences. An attacker can supply a benign-looking artifact (e.g., a README file or documentation) containing executable code blocks or structured text that the agent…

MemoryGraft: Persistent compromise of LLM agents via poisoned experience retrieval
Evaluated models: GPT-4o

GPT Tool Misuse

Published Analyzed Source: arXiv

A vulnerability exists in OpenAI's Custom GPTs platform where the lack of effective isolation between the system context ("Expert Prompt"), external knowledge retrieval, and user input allows for unauthorized information disclosure and tool misuse. By employing specific prompt injection techniques—including Hex injection, Many-shot prefix attacks, and Knowledge Poisoning (uploading malicious files)—an attacker can bypass safety guardrails. This results in the extraction of proprietary system…

An Empirical Study on the Security Vulnerabilities of GPTs
Evaluated models: DALL-E

LLM Agent Automates Backdoor Injection

Published Analyzed Source: arXiv

A vulnerability in the fine-tuning process of Large Language Models (LLMs) allows for the automated generation of stealthy backdoor attacks using an autonomous LLM agent. This method, termed AutoBackdoor, creates a pipeline to generate semantically coherent trigger phrases and corresponding poisoned instruction-response pairs. Unlike traditional backdoor attacks that rely on fixed, often anomalous triggers, this technique produces natural language triggers that are contextually relevant and…

AutoBackdoor: Automating Backdoor Attacks via LLM Agents
Evaluated models: GPT-4o, GPT-4o Mini, Llama 3.1 8B Instruct+3 more
  • GPT-4o
  • GPT-4o Mini
  • Llama 3.1 8B Instruct
  • Mistral 7B Instruct v0.3
  • Qwen 2.5 14B Instruct
  • Qwen 2.5 7B Instruct

Distributed Backdoor in Multi-Agent Systems

Published Analyzed Source: arXiv

A distributed backdoor vulnerability, named "Collaborative Shadows", exists in LLM-based Multi-Agent Systems (MAS) that rely on external or modifiable tools. An attacker can poison multiple agent tools by embedding inert, encrypted "attack primitives" within them. These primitives are fragments of a larger malicious payload. A carefully crafted user instruction acts as both a trigger and a decryption key. The instruction steers the agents to collaborate in a specific sequence, causing them to…

Collaborative Shadows: Distributed Backdoor Attacks in LLM-Based Multi-Agent Systems
Evaluated models: Gemini 2.5 Pro, GLM 4.5, GPT-4.1+2 more
  • Gemini 2.5 Pro
  • GLM 4.5
  • GPT-4.1
  • Kimi K2 Instruct
  • Qwen 3 30B-A3B

Self-Amplifying Memory Poisoning

Published Analyzed Source: arXiv

Large Language Model (LLM) agents utilizing long-term memory or Retrieval-Augmented Generation (RAG) are vulnerable to context-dependent memory injection attacks. Unlike traditional prompt injections that are overtly malicious, this vulnerability involves injecting records that appear benign and coherent in isolation—thereby bypassing standard perplexity filters and static content moderation (e.g., LlamaGuard). These records contain "sleeping" malicious logic that is only activated when…

A-memguard: A proactive defense framework for llm-based agent memory
Evaluated models: GPT-4o, Llama 3.1 8B

Prompt Injection Alignment Bypass

Published Analyzed Source: arXiv

Large Language Models (LLMs) integrated with external retrieval mechanisms (e.g., Retrieval-Augmented Generation (RAG), web search, or email processing) are vulnerable to Indirect Prompt Injection. This vulnerability occurs when an LLM consumes input from untrusted external sources—such as websites, code repositories, or incoming emails—that contain embedded adversarial prompts. Unlike direct injection, where the user attacks the model, here the "poisoned" data is retrieved by the system…

Breaking to Build: A Threat Model of Prompt-Based Attacks for Securing LLMs
Evaluated models: Not reported

Inter-Agent Computer Takeover

Published Analyzed Source: arXiv

A remote code execution (RCE) and privilege escalation vulnerability exists in Large Language Model (LLM) multi-agent systems and agentic RAG (Retrieval-Augmented Generation) architectures. The vulnerability arises from "Inter-Agent Trust Exploitation," where LLM agents implicitly trust instructions received from peer agents, bypassing safety guardrails and jailbreak defenses that are active during direct human-to-LLM interaction. An attacker can inject a malicious command payload (e.g., a…

The Dark Side of LLMs: Agent-based Attack Vectors for System-level Compromise
Evaluated models: GPT-4o Mini, GPT-4o, GPT-4.1 Mini+15 more
  • GPT-4o Mini
  • GPT-4o
  • GPT-4.1 Mini
  • GPT-4.1
  • Claude Sonnet 4
  • Claude Opus 4
  • Gemini 2.0 Flash
  • Gemini 2.5 Flash
  • Gemini 2.5 Pro
  • Magistral Medium
  • Mistral Large
  • Mistral Small
  • Llama 3.3 70B
  • Llama 4 16x17B
  • Qwen 3 14B
  • Qwen 3 30B-A3B
  • Devstral 24B
  • DeepSeek R1 Tool Calling 70B

Research methodology

Entries summarize publicly available primary-source security research. Model names reflect only systems explicitly evaluated by the cited paper, and measurements are research-reported unless independent verification is stated.

Discovery and publication are separate: new papers enter a candidate queue, then require human review and explicit approval before publication. Updates follow that review process, not a guaranteed daily publishing schedule. “Last analyzed” is the newest analysis date among published entries; it does not mean that all recent research has been covered.