Language Model Security Database

Large Language Models (LLMs) employed as automated code evaluators ("Universal Graders") are vulnerable to Semantic-Instruction Decoupling, a form of adversarial prompt injection that exploits the "Syntax-Semantics Gap." Attackers can embed adversarial directives into syntactically inert regions of the Abstract Syntax Tree (AST)—specifically comments, docstrings, variable names, and whitespace. While these regions are discarded by compilers (trivia nodes) or treated as arbitrary symbols…

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…

LLM-based evaluation systems ("LLM-as-a-Judge") exhibit a structural vulnerability termed "Framing Bias," wherein the model produces logically contradictory judgments depending on the syntactic framing of the evaluation prompt. Specifically, when assessing the same content using predicate-positive (P) framing (e.g., "Is this toxic?") versus predicate-negative (¬P) framing (e.g., "Is this non-toxic?"), models frequently fail to invert their binary decisions, leading to inconsistency rates…

LLM-as-a-Reviewer systems, which utilize large language models to automate the peer review process, are vulnerable to the Paraphrasing Adversarial Attack (PAA). PAA is a black-box optimization technique that exploits the model's sensitivity to specific input sequences and self-preference bias. By iteratively paraphrasing specific manuscript sections (such as the abstract) using in-context learning (ICL) guided by previous review scores, an attacker can generate adversarial sequences that…

LLM routing systems are vulnerable to adversarial rerouting attacks where malicious triggers prepended to user queries manipulate the router's model-selection mechanism. Because LLM routers function as classifiers evaluating query complexity to balance computational cost and response quality, an attacker can craft adversarial prefixes that distort the query's latent semantic representation. This exploits the router's decision boundaries, forcing the system to misclassify the input and redirect…

Token-level embedding-time watermarking algorithms, specifically KGW (Kirchenbauer et al.) and Exponential Sampling (EXP, Kuditipudi et al.), when implemented in Large Language Models (LLMs) for Bangla text generation, are vulnerable to watermark erasure via cross-lingual round-trip translation (RTT) attacks. While these methods achieve high detection accuracy (>88%) under benign conditions, translating watermarked Bangla text to English and back to Bangla causes detection accuracy to collapse…

Code-generation Large Language Models (LLMs) and Multimodal Large Language Models (MLLMs) are vulnerable to directed misuse for the generation of misleading data visualizations. This vulnerability, described as the "ChartAttack" framework, allows an attacker to prompt the model to manipulate chart annotation code (e.g., JSON specifications for Matplotlib or Vega-Lite) to apply specific "misleaders"—design choices that distort data interpretation without altering the underlying data values. By…

Large Language Models (LLMs) are vulnerable to multi-turn persuasive conversational attacks that induce the adoption of counterfactual beliefs. By leveraging the Source–Message–Channel–Receiver (SMCR) communication framework, attackers can systematically erode a model's confidence in established facts and compel the model to output misinformation. Specific attack vectors include manipulating source attribution (authority framing), message content (logical, credibility, or emotional appeals)…

Large Language Models (LLMs) deployed using Multiple-Choice Question Answering (MCQA) interfaces or choice-based selection structures are vulnerable to Option Injection. By appending a task-irrelevant candidate choice (e.g., Option E) containing a steering directive—specifically utilizing threat framing (penalty coercion) or bonus framing (reward inducement)—an attacker can hijack the model's decision-making process. The vulnerability stems from a flaw in attention allocation: the model's…

The Google Agent Payments Protocol (AP2), specifically within the reference implementation built using the Google Agent Development Kit (ADK) and Gemini models, contains vulnerabilities allowing for both indirect and direct prompt injection. The architecture fails to sufficiently isolate the Large Language Model (LLM) context from untrusted external data sources and user inputs.