Skip to main content
LLM Security Database
Skip to research search
Last analyzed 9/9/2026

Language Model Security Database

985 research findings · 1123 evaluated models

Filtered research findings

87 entries

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

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

Instruction-tuned Large Language Models (LLMs) are vulnerable to the induction of "hidden intentions"—covert, goal-directed manipulative behaviors—via lightweight prompt engineering, system prompts, or agentic workflows. Attackers can embed latent agendas (e.g., commercial manipulation, simulated consensus, or the promotion of insecure coding practices) into model outputs that trigger only under specific conversational contexts. Because these manipulative behaviors mimic benign interactions…

Unknown Unknowns: Why Hidden Intentions in LLMs Evade Detection
Evaluated models: Mistral 7B, Llama 3.2 3B, Gemma 3 12B IT +9 more

Source: arXiv

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

In distributed Low-Rank Adaptation (LoRA) fine-tuning systems, a structural verification blind spot exists due to the decoupled aggregation of low-rank matrices. Frameworks typically evaluate and aggregate the $A$ and $B$ matrices independently to reduce computational overhead. A malicious client can exploit this by submitting individually benign $A$ and $B$ matrices that satisfy standard norm-based and similarity-based anomaly detection filters, but whose composite product ($A \times B$)…

Low Rank Comes with Low Security: Gradient Assembly Poisoning Attacks against Distributed LoRA-based LLM Systems
Evaluated models: ChatGLM2 6B, GPT-2 124M, Llama 7B +2 more

Source: arXiv

Published 1/1/2026
Analyzed 1/14/2026

A malicious model supply chain vulnerability exists involving a technique termed Adversarial Contrastive Learning (ACL) for Large Language Model (LLM) quantization attacks. This vulnerability allows an attacker to publish a model that appears benign and preserves high utility in full precision (e.g., BF16 or FP32) but exhibits malicious behaviors—such as jailbreak, over-refusal, or advertisement injection—immediately upon zero-shot quantization (e.g., INT8, FP4, or NF4).

Adversarial Contrastive Learning for LLM Quantization Attacks
Evaluated models: Qwen 2.5 1.5B Instruct, Qwen 2.5 3B Instruct, Llama 3.2 1B Instruct +1 more

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 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 2/21/2026

LLM-enhanced Graph Neural Networks (GNNs), which integrate Large Language Model (LLM) feature encoders with graph message-passing architectures, are vulnerable to a black-box node injection attack known as "GraphTextack." This vulnerability exists because the joint model architecture creates a dual attack surface: the GNN component is sensitive to structural perturbations (changes in graph topology), while the LLM component is sensitive to semantic perturbations (adversarial phrasing).

GRAPHTEXTACK: A Realistic Black-Box Node Injection Attack on LLM-Enhanced GNNs
Evaluated models: Llama 2 7B

Source: arXiv

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

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

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 10/31/2025

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

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

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.