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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.

The Adaptive Greedy Binary Search (AGBS) framework exposes a vulnerability in Large Language Models (LLMs) regarding their susceptibility to semantic-preserving adversarial attacks. The vulnerability is exploited through a hierarchical decomposition strategy that identifies key semantic units (clauses and keywords) within a prompt. AGBS utilizes a dynamic threshold mechanism to adjust semantic similarity bounds in real-time during a beam search process, replacing tokens with candidates that…

Semantic-Preserving Prompt Hijacking: A Black-Box Adversarial Attack on Auto-Prompt Optimization
Affects: GPT-3.5 Turbo, GPT-4 Turbo, GPT-4o +7 more

Source: arXiv

Large Language Models (LLMs), specifically Transformer-based architectures, are vulnerable to an attention hijacking attack via optimized adversarial suffixes. The vulnerability resides in the shallow information flow mechanism of the attention layer, where specific token sequences (adversarial suffixes) can exert irregular and extreme dominance over the internal representation of the final chat template tokens immediately preceding generation. This "hijacking" suppresses the representation of…

Universal Jailbreak Suffixes Are Strong Attention Hijackers
Affects: Gemma 2 2B IT, Qwen 2.5 0.5B Instruct, Qwen 2.5 1.5B Instruct +2 more

Source: arXiv

VERA, a variational inference framework, enables the generation of diverse and fluent adversarial prompts that bypass safety mechanisms in large language models (LLMs). The attacker model, trained through a variational objective, learns a distribution of prompts likely to elicit harmful responses, effectively jailbreaking the target LLM. This allows for the generation of novel attacks that are not based on pre-existing, manually crafted prompts.

VERA: Variational Inference Framework for Jailbreaking Large Language Models
Affects: Baichuan 2 7B, Gemini Pro, GPT-3.5 Turbo +8 more

Source: arXiv

Large Language Models (LLMs) are vulnerable to adaptive jailbreaking attacks that exploit their semantic comprehension capabilities. The MEF framework demonstrates that by tailoring attacks to the model's understanding level (Type I or Type II), evasion of input, inference, and output-level defenses is significantly improved. This is achieved through layered semantic mutations and dual-ended encryption techniques, allowing bypass of security measures even in advanced models like GPT-4o.

Adaptive Jailbreaking Strategies Based on the Semantic Understanding Capabilities of Large Language Models
Affects: GPT-4o, Llama 2 13B, Llama 2 7B

Source: arXiv

Large Reasoning Models (LRMs) utilizing Chain-of-Thought (CoT) processes are vulnerable to an adaptive stacked cipher attack known as SEAL (Stacked Encryption for Adaptive Language reasoning model jailbreak). The vulnerability arises because the model's reasoning capabilities effectively function as a decryption engine, processing complex multi-layered obfuscations (e.g., stacked combinations of Caesar, Base64, ASCII, HEX, and reversal ciphers) that bypass input-level safety filters. By…

Three Minds, One Legend: Jailbreak Large Reasoning Model with Adaptive Stacked Ciphers
Affects: DeepSeek R1, o1-mini, o4-mini +3 more

Source: arXiv

Large Language Models (LLMs), specifically instruction-tuned variants, are vulnerable to safety guardrail bypass via adversarial suffix injection. By appending a specific sequence of tokens—often semantically meaningless characters or carefully crafted distractors—to a malicious query, an attacker can manipulate the model's internal representation to override alignment training (RLHF). This coercion causes the model to affirmatively respond to otherwise refused requests, such as generating…

Adversarial Suffix Filtering: a Defense Pipeline for LLMs
Affects: GPT-3.5, GPT-4o, Llama 2 7B +2 more

Source: arXiv

End-to-end Large Audio-Language Models (LALMs) are vulnerable to AudioJailbreak, a novel attack that appends adversarial audio perturbations ("jailbreak audios") to user prompts. These perturbations, even when applied asynchronously and without alignment to the user's speech, can manipulate the LALM's response to generate adversary-desired outputs that bypass safety mechanisms. The attack achieves universality by employing a single perturbation effective across different prompts and robustness…

AudioJailbreak: Jailbreak Attacks against End-to-End Large Audio-Language Models
Affects: BLSP, FunAudioLLM, GPT-4o +9 more

Source: arXiv

Chain-of-thought (CoT) reasoning, while intended to improve safety, can paradoxically increase the harmfulness of successful jailbreak attacks by enabling the generation of highly detailed and actionable instructions. Existing jailbreaking methods, when applied to LLMs employing CoT, can elicit more precise and dangerous outputs than those from LLMs without CoT.

Does Chain-of-Thought Reasoning Really Reduce Harmfulness from Jailbreaking?
Affects: Claude 3.5 Sonnet, DeepSeek Chat, DeepSeek R1 +9 more

Source: arXiv

A vulnerability exists in multiple large language and multimodal models that allows for the bypass of safety filters through the use of code-mixed prompts with phonetic perturbations. An attacker can craft a prompt in a code-mixed language (e.g., Hinglish) and apply phonetic misspellings to sensitive keywords (e.g., spelling "hate" as "haet"). This technique causes the model's tokenizer to parse the sensitive word into benign sub-tokens, preventing safety mechanisms from flagging the harmful…

" Haet Bhasha aur Diskrimineshun": Phonetic Perturbations in Code-Mixed Hinglish to Red-Team LLMs
Affects: Gemma 1.1 7B IT, GPT-4o, GPT-4o Mini +2 more

Source: arXiv

Updated 12/8/2025

The SPECTRE framework introduces a black-box adversarial attack vector against Large Language Models (LLMs) that utilizes malicious system prompts to hijack conversations. Unlike traditional jailbreaks that aim to bypass safeguards for all inputs, SPECTRE optimizes system prompts to induce incorrect or harmful responses only for specific targeted questions (e.g., "Are COVID vaccines safe?", "Who should I vote for?"), while maintaining high accuracy and benign behavior on all other non-targeted…

SPECTRE: Conditional System Prompt Poisoning to Hijack LLMs
Affects: GPT-3.5 Turbo, GPT-4o Mini, Llama 2 7B +8 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.