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Updated 7/21/2026, database is current

Language Model Security Database

959 research findings · 1077 evaluated models

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599 entries

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

Updated 11/20/2025

A jailbreak vulnerability, known as Task Concurrency, exists in multiple Large Language Models (LLMs). The vulnerability arises when two distinct tasks, one harmful and one benign, are interleaved at the word level within a single prompt. The structure of the malicious prompt alternates words from each task, often using separators like {} to encapsulate words from the second task. This "concurrent" instruction format obfuscates the harmful intent from the model's safety guardrails, causing the…

Adjacent Words, Divergent Intents: Jailbreaking Large Language Models via Task Concurrency
Affects: DeepSeek V3, Gemini 2.5 Flash, GPT-4.1 +7 more

Source: arXiv

A vulnerability termed "Controlled-Release Prompting" allows attackers to bypass lightweight input filters (prompt guards) deployed in front of Large Language Models (LLMs). The attack exploits the computational resource asymmetry between the resource-constrained guard model and the highly capable target model. Attackers encode malicious instructions using obfuscation techniques—such as substitution ciphers (Timed-Release) or verbose character descriptions (Spaced-Release)—that require…

Bypassing Prompt Guards in Production with Controlled-Release Prompting
Affects: Gemini 2.5 Flash, Gemini 2.5 Pro, DeepSeek R1 +2 more

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
Affects: Gemini 2.5 Pro, GLM 4.5, GPT-4.1 +2 more

Source: arXiv

A "Priming Vulnerability" exists in Masked Diffusion Language Models (MDLMs) due to their iterative, parallel denoising inference mechanism. Unlike autoregressive models that generate tokens sequentially, MDLMs refine a sequence from a fully masked state through multiple denoising steps. The vulnerability arises because standard safety alignment (e.g., SFT, DPO, MOSA) typically optimizes the model to generate safe responses only when initialized from a fully masked sequence. If an affirmative…

Toward Safer Diffusion Language Models: Discovery and Mitigation of Priming Vulnerability

Source: arXiv

LLM-based coding agents integrated into IDEs (e.g., VS Code Copilot, Cursor, Windsurf) are vulnerable to a query-agnostic Indirect Prompt Injection (IPI) attack termed "QueryIPI." This vulnerability allows an attacker to achieve Remote Code Execution (RCE) on the developer's machine by injecting a malicious tool definition (e.g., via the Model Context Protocol) into the agent's context.

QueryIPI: Query-agnostic Indirect Prompt Injection on Coding Agents
Affects: Claude Sonnet 4

Source: arXiv

Large Language Models (LLMs) are vulnerable to imperceptible jailbreaking attacks and prompt injection via the exploitation of Unicode variation selectors. This vulnerability arises from a discrepancy between text rendering and tokenizer processing. Attackers can append long sequences of invisible variation selectors (specifically from ranges U+FE00–U+FE0F and U+E0100–U+E01EF) to malicious prompts. While these characters are visually rendered as zero-width or ignored by standard user…

Imperceptible Jailbreaking against Large Language Models
Affects: Llama 2 7B, Llama 3.1 8B, Mistral 7B +1 more

Source: arXiv

Large Language Model (LLM) integrated agents and applications are vulnerable to Prompt Injection attacks where untrusted data (e.g., retrieved documents, tool outputs, website content) overrides system instructions. Because LLMs typically process instructions and data within a single context window without strict separation, an attacker can embed imperative commands within the data channel. This vulnerability extends beyond simple overriding instructions; it includes sophisticated techniques…

Defending against prompt injection with datafilter
Affects: GPT-4o, Llama 3.1 8B Instruct

Source: arXiv

A security vulnerability exists in the safety alignment mechanisms of Large Language Models (LLMs), specifically susceptible to the "Dynamic Target Attack" (DTA). Unlike traditional gradient-based jailbreaks (e.g., GCG) that optimize adversarial suffixes toward a fixed, low-probability static target (e.g., "Sure, here is..."), DTA exploits the model's own output distribution. The attack iteratively samples candidate responses from the target model using relaxed decoding parameters (high…

Dynamic Target Attack
Affects: Llama 3 8B, Llama 3.2 1B, Mistral 7B +3 more

Source: arXiv

Reasoning segmentation models, which generate binary segmentation masks based on implicit text queries, are vulnerable to adversarial paraphrasing. This vulnerability allows an attacker to craft semantically equivalent and grammatically correct text prompts that significantly degrade the model's segmentation performance (measured by Intersection-over-Union, or IoU). The exploit utilizes a black-box, sentence-level optimization method (SPARTA) that operates within the continuous semantic latent…

SPARTA: Evaluating Reasoning Segmentation Robustness through Black-Box Adversarial Paraphrasing in Text Autoencoder Latent Space
Affects: LISA 7B, LISA Explanatory 7B, LISA 13B +3 more

Source: arXiv

Large Language Models (LLMs), specifically variants of GPT-4o, DeepSeek-R1, OLMo-2, and Llama-4, are vulnerable to accelerated adaptive adversarial attacks due to excessive information leakage in observable output signals. When these models expose "thinking processes" (Chain-of-Thought traces) or token-level log-probabilities (logits) to the end user, they leak significant mutual information $I(Z;T)$ regarding the model's safety state or hidden instructions. This leakage allows adaptive attack…

Bits Leaked per Query: Information-Theoretic Bounds on Adversarial Attacks against LLMs
Affects: DeepSeek R1, GPT-4o Mini 2024-07-18, Llama 4 Maverick 17B +4 more

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.