The paper reports a reproducible black-box evaluation showing that adversarial user queries can cause deployed LLM applications to reveal hidden system prompts. In the authors’ measurement of 1,200 applications across six commercial platforms, 1,064 applications leaked prompt content (81.0%–93.5% per anonymized platform). This is a paper-reported result, not independently verified here. LeakBench and the official artifact repository provide defensive benchmark materials for controlled testing…
Understanding and Mitigating Prompt Leaking Attacks in Real-World LLM-Based Applications
OpenClaw is vulnerable to persistent memory poisoning, allowing an attacker to manipulate the agent's long-term memory store (MEMORY.md) via prompt injection. Because the autonomous agent continuously integrates this memory file as context for all subsequent reasoning and task planning, injected payloads act as durable behavioral constraints. This allows an attacker to persistently alter the agent's core policy, manipulate tool selection, and hijack future sessions without any further…
Taming openclaw: Security analysis and mitigation of autonomous llm agent threats
Large Language Models (LLMs) are vulnerable to system instruction leakage when extraction requests are framed as benign formatting, encoding, or structured-output tasks. While standard alignment and refusal mechanisms successfully block direct queries for system instructions, they fail when attackers request the instructions to be rendered in alternate representations (e.g., YAML, TOML, Base64, or system logs). The model's safety filters misinterpret the request as a harmless transformation or…
Automated Framework to Evaluate and Harden LLM System Instructions against Encoding Attacks
Evaluated models: GPT-4.1 Mini, GPT-3.5 Turbo, Gemini 2.5 Flash+1 more
An Indirect Prompt Injection (IPI) vulnerability exists in reasoning-enhanced Large Language Models (LLMs) when processing untrusted external documents, such as resumes in Applicant Tracking Systems (ATS). Unlike standard instruction-tuned models that resort to easily detectable factual hallucinations when injected, reasoning models utilizing Chain-of-Thought (CoT) architectures weaponize their inference capabilities to construct highly persuasive, unfaithful post-hoc rationalizations. They…
Trojan Horses in Recruiting: A Red-Teaming Case Study on Indirect Prompt Injection in Standard vs. Reasoning Models
Agentic LLM systems that automatically preview URLs or extract web metadata are vulnerable to implicit prompt injection, resulting in silent data exfiltration ("silent egress"). Attackers can embed adversarial instructions in unobserved web elements, such as HTML <title> tags, <meta> descriptions, or Open Graph metadata. When a user requests a summary of the URL—or when the agent automatically unfurls a linked URL in a chat—the system fetches the malicious page and flattens this metadata into…
Silent Egress: When Implicit Prompt Injection Makes LLM Agents Leak Without a Trace
A vulnerability exists in the tool selection mechanisms of Large Language Model (LLM) agents, identified as the "Attractive Metadata Attack" (AMA). This flaw allows an adversary to manipulate the metadata (names, descriptions, and parameter schemas) of malicious external tools to statistically maximize the likelihood of their selection by the agent, without requiring prompt injection or access to model internals. The vulnerability exploits the agent’s semantic scoring function used to map user…
Attractive Metadata Attack: Inducing LLM Agents to Invoke Malicious Tools
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…
Just Ask: Curious Code Agents Reveal System Prompts in Frontier LLMs
Evaluated models: o1, Llama 3.1 70B Hanami X1, Phi-4+38 more
A black-box guardrail reverse-engineering vulnerability exists in Large Language Model (LLM) serving systems that employ output filtering mechanisms. The vulnerability allows remote attackers to replicate the proprietary decision-making policy and rule sets of the target's safety guardrail without direct access to model parameters. This is achieved through a technique termed Guardrail Reverse-engineering Attack (GRA), which utilizes a reinforcement learning framework combined with genetic…
Fine-tuning Large Language Models (LLMs) on the CyberLLMInstruct dataset results in a critical degradation of safety alignment and refusal mechanisms. While the dataset comprises "pseudo-malicious" content (educational descriptions of malware, phishing, and exploits without executable payloads), the Supervised Fine-Tuning (SFT) process on this corpus causes the models to generalize this instruction-following behavior to actual malicious requests. This effectively bypasses safety guardrails…
CyberLLMInstruct: A new dataset for analysing safety of fine-tuned LLMs using cyber security data