Language Model Security Database

A vulnerability exists in LLM-based Multi-Agent Systems (LLM-MAS) where an attacker with control over the communication network can perform a multi-round, adaptive, and stealthy message tampering attack. By intercepting and subtly modifying inter-agent messages over multiple conversational turns, an attacker can manipulate the system's collective reasoning process. The attack (named MAST in the reference paper) uses a fine-tuned policy model to generate a sequence of small, context-aware…

Large Reasoning Models (LRMs) can be instructed via a single system prompt to act as autonomous adversarial agents. These agents engage in multi-turn persuasive dialogues to systematically bypass the safety mechanisms of target language models. The LRM autonomously plans and executes the attack by initiating a benign conversation and gradually escalating the harmfulness of its requests, thereby circumventing defenses that are not robust to sustained, context-aware persuasive attacks. This…

A targeted adversarial attack vulnerability exists in Multimodal Large Language Models (MLLMs) susceptible to Adversarial-Guided Diffusion (AGD). This technique generates adversarial images by injecting targeted semantic information into the noise component of the reverse-diffusion process within a text-to-image generative model (specifically Stable Diffusion). Unlike traditional pixel-based attacks that introduce high-frequency perturbations easily removed by low-pass filtering, AGD utilizes…

LLM-powered agentic systems that use external tools are vulnerable to prompt injection attacks that cause them to bypass their explicit policy instructions. The vulnerability can be exploited through both direct user interaction and indirect injection, where malicious instructions are embedded in external data sources processed by the agent (e.g., documents, API responses, webpages). These attacks cause agents to perform prohibited actions, leak confidential data, and adopt unauthorized…

A vulnerability exists where Large Language Models (LLMs) can be manipulated by prepending a specially crafted 'persona prompt', often in the system prompt. These persona prompts cause the model to shift its attention from sensitive keywords in a harmful request to the stylistic instructions of the persona. This weakens the model's safety alignment, significantly reducing its refusal rate for harmful queries. The vulnerability is particularly severe because these persona prompts have a…

A vulnerability exists in Large Language Diffusion Models (LLDMs) due to their parallel denoising architecture. The PArallel Decoding (PAD) jailbreak attack exploits this architecture by injecting multiple, semantically innocuous "sequence connectors" (e.g., "Step 1:", "First") at distributed locations within the initial masked sequence. During the parallel denoising process, these injected tokens act as anchor points that bias the probability distribution of adjacent token predictions. This…

LLM agents integrating with external environments (e.g., via tool use, web retrieval, or RAG) are vulnerable to indirect prompt injection attacks. Malicious instructions embedded in untrusted data sources—such as emails, webpages, or tool outputs—are ingested by the agent and treated as valid context. Because the backend Large Language Model (LLM) struggles to distinguish between system instructions, user instructions, and third-party data, these embedded prompts can hijack the execution flow…

Large Language Model (LLM) systems integrated with private enterprise data, such as those using Retrieval-Augmented Generation (RAG), are vulnerable to multi-stage prompt inference attacks. An attacker can use a sequence of individually benign-looking queries to incrementally extract confidential information from the LLM's context. Each query appears innocuous in isolation, bypassing safety filters designed to block single malicious prompts. By chaining these queries, the attacker can…

Retrieval-Augmented Generation (RAG) systems utilizing dense (e.g., BERT-based) or sparse (e.g., BM25) retrievers are vulnerable to black-box adversarial prompt injection attacks. By employing a gradient-free Differential Evolution (DE) optimization algorithm (referred to as DeRAG), an attacker can generate short adversarial suffixes (typically ≤ 5 tokens). When these suffixes are appended to a user query, they manipulate the retriever's ranking mechanism to promote a specific, malicious, or…

Large Language Models (LLMs) are vulnerable to a jailbreak attack termed Paper Summary Attack (PSA). An attacker can bypass safety alignment mechanisms by framing a harmful query within the context of a summarized academic paper. The model's propensity to trust the authoritative structure and tone of a research paper summary overrides its safety filters, leading it to process and respond to the embedded malicious instruction. The vulnerability is particularly potent when using summaries of…