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Last analyzed 9/9/2026

Language Model Security Database

985 research findings · 1123 evaluated models

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41 entries

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

Published 1/1/2026
Analyzed 3/8/2026

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

Source: arXiv

Published 1/1/2026
Analyzed 3/9/2026

Web-facing Retrieval-Augmented Generation (RAG) systems are vulnerable to Indirect Prompt Injection (IPI) and retrieval poisoning via web-native markup and Unicode carriers. Standard ingestion pipelines often parse untrusted web pages without stripping invisible constructs, such as hidden HTML spans, off-screen CSS, alt text, ARIA attributes, and zero-width characters. When an attacker embeds malicious instructions within these invisible carriers on third-party sites, the RAG system retrieves…

Hidden-in-Plain-Text: A Benchmark for Social-Web Indirect Prompt Injection in RAG
Evaluated models: Llama 3 8B, Mistral 7B, Qwen 2.5 14B

Source: arXiv

Published 1/1/2026
Analyzed 2/22/2026

Neural Ranking Models (NRMs) utilizing Transformer architectures (specifically BERT and T5-based re-rankers) are vulnerable to minimal adversarial perturbations that artificially promote a target document's rank. The vulnerability allows an attacker to manipulate ranking outcomes by inserting or substituting a single "query center" token—a word identified as the semantic centroid of the user's query—into the target document. The attack exploits the model's sensitivity to specific semantic…

One Word is Enough: Minimal Adversarial Perturbations for Neural Text Ranking
Evaluated models: Not reported

Source: arXiv

Published 12/1/2025
Analyzed 12/8/2025

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

Source: arXiv

Published 12/1/2025
Analyzed 2/21/2026

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

Source: arXiv

Published 11/1/2025
Analyzed 12/30/2025

A data poisoning vulnerability exists in the Retrieval-Augmented Generation (RAG) component of Large Language Model (LLM)-based Network Intrusion Detection Systems (NIDS). The vulnerability allows an attacker to inject adversarially perturbed text into the system's knowledge base. By employing a transfer-learning attack using a surrogate model (e.g., BERT) and word-level perturbation algorithms (e.g., TextFooler), an attacker can generate semantic-preserving descriptions that alter the vector…

RAG-targeted Adversarial Attack on LLM-based Threat Detection and Mitigation Framework
Evaluated models: Not reported

Source: arXiv

Published 10/1/2025
Analyzed 1/14/2026

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

Source: arXiv

Published 9/1/2025
Analyzed 12/9/2025

Retrieval-Augmented Generation (RAG) systems in the health domain are vulnerable to corpus poisoning attacks where adversarial documents—specifically those generated via "Liar" (fabricated from scratch based on an incorrect stance) and "Few-Shot Adversarial Prompting" (FSAP)—are injected into the retrieval pool. When these adversarial documents are retrieved and presented as context, they successfully override the Large Language Model's (LLM) internal safety alignment and ground-truth…

Evaluating the Robustness of Retrieval-Augmented Generation to Adversarial Evidence in the Health Domain
Evaluated models: GPT-4.1, GPT-5, Claude 3.5 Haiku +3 more

Source: arXiv

Published 9/1/2025
Analyzed 12/8/2025

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

Source: arXiv

Published 8/1/2025
Analyzed 12/30/2025

Retrieval-Augmented Generation (RAG) systems are vulnerable to knowledge poisoning attacks (specifically the "PoisonedRAG" method) where an attacker injects adversarial texts into the retrieval knowledge database. These adversarial texts are optimized to achieve two simultaneous goals: 1) rank highly (top-k) during the retrieval phase for specific target queries, and 2) semantically steer the Large Language Model (LLM) to generate a pre-defined, attacker-chosen response instead of the ground…

Defending against knowledge poisoning attacks during retrieval-augmented generation
Evaluated models: GPT-3.5, GPT-4, GPT-4o

Source: arXiv

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.