Language Model Security Database

LLaMA-series models (specifically evaluated on LLaMA-1B and LLaMA-3B) exhibit memorization of structured recommender system training data, specifically the MovieLens-1M dataset. While manual prompting yields inconsistent results, the application of Automatic Prompt Engineering (APE)—which treats prompt design as an optimization problem using iterative refinement—allows for the successful extraction of item-level training data (e.g., movie titles and genres) with exact-match accuracy surpassing…

A vulnerability exists in Large Language Model (LLM) deployments and multi-agent systems where an autonomous attacker agent can systematically extract hidden system prompts through self-evolving interaction strategies. The vulnerability leverages a "JustAsk" framework which utilizes Upper Confidence Bound (UCB) exploration to dynamically select and refine attack vectors from a hierarchical taxonomy of 14 atomic skills (e.g., structural formatting, authority appeals) and 14 multi-turn…

A multi-turn jailbreak vulnerability exists in multiple state-of-the-art Large Language Models (LLMs) that allows attackers to bypass safety guardrails by progressively steering long-horizon conversations. Demonstrated via the "Mastermind" framework, the attack leverages a hierarchical multi-agent architecture to decouple high-level malicious objectives from low-level tactical execution. By employing strategy-level fuzzing—dynamically reflecting on model refusals and recombining abstracted…

Safety-aligned Large Language Models (LLMs) are vulnerable to Best-of-N (BoN) sampling attacks, where adversaries bypass safety guardrails by systematically executing large-scale, parallel queries with prompt variations until a harmful response is elicited. The scaling behavior of attack success rates (ASR) demonstrates that models appearing robust under standard single-shot or low-budget evaluations experience rapid, non-linear risk amplification under parallel adversarial pressure. Because…

Large Vision-Language Models (LVLMs), specifically InstructBLIP, LLaVA, and MiniGPT-4, are susceptible to a black-box adversarial jailbreak vulnerability via Zeroth-Order Simultaneous Perturbation Stochastic Approximation (ZO-SPSA). An attacker can generate adversarial images with imperceptible perturbations that, when paired with harmful text prompts, bypass the model's safety alignment mechanisms (such as RLHF). Unlike traditional white-box attacks, this method does not require access to…

Lightweight Chinese Large Language Models (LLMs) are vulnerable to jailbreaking attacks that employ language-specific linguistic obfuscation techniques. Standard safety guardrails, which typically rely on keyword detection or semantic analysis of clean text, fail to identify malicious intent when sensitive terms are disguised using Chinese-specific adversarial patterns. These patterns include Pinyin Mix (replacing characters with Romanized phonetic spellings), Homophones (substituting visually…

A vulnerability exists in Large Language Model (LLM) and Large Reasoning Model (LRM) serving interfaces that allow user-defined response prefixes, such as plain text-completion (v1/completions), Fill-in-the-Middle (FIM), or assistant message prefilling. An attacker can perform a Response Prefix Attack (RPA) by injecting maliciously crafted Chain-of-Thought (CoT) reasoning tokens immediately following the assistant's start delimiter (e.g., <|im_start|>assistant). Because these tokens are placed…

Large Reasoning Models (LRMs) employing Chain-of-Thought (CoT) generation are vulnerable to sensitive information leakage through intermediate reasoning steps, even after undergoing standard unlearning procedures (such as Gradient Ascent, Direct Preference Optimization, or KL Minimization). While these fine-tuning-based unlearning methods typically suppress sensitive content in the final generated answer, they fail to purge the information from the model's internal reasoning trajectory…

A vulnerability in large language models (LLMs) allows attackers to induce factually incorrect outputs by injecting misinformation into prompts framed with strong confidence. By using authoritative phrasing (e.g., "As we know..."), attackers exploit model sycophancy, causing the LLM to accept the false premise and generate hallucinated content aligned with the injected misinformation. The models fail to detect and correct the embedded falsehoods, generating fabricated but plausible responses.

A vulnerability exists in frontier Large Language Models (LLMs) where in-context information (e.g., provided via Retrieval-Augmented Generation) completely overrides parametric safety guardrails when processing counterfactual or adversarial medical evidence. When a prompt contains fabricated clinical context asserting the medical efficacy of toxic substances, illicit drugs, or nonsensical items, the LLM suppresses its internal knowledge of the substance's toxicity. Internal representation…