All news with #llm tag

MCP Sampling Risks: New Prompt-Injection Attack Vectors

🔒 This Unit 42 investigation (published December 5, 2025) analyzes security risks introduced by the Model Context Protocol (MCP) sampling feature in a popular coding copilot. The authors demonstrate three proof-of-concept attacks—resource theft, conversation hijacking, and covert tool invocation—showing how malicious MCP servers can inject hidden prompts and trigger unobserved model completions. The report evaluates detection techniques and recommends layered mitigations, including request sanitization, response filtering, and strict access controls to protect LLM integrations.

Indirect Prompt Injection Poisons Agents' Long-Term Memory

⚠️This Unit 42 proof-of-concept shows how an attacker can use indirect prompt injection to silently poison an AI agent’s long-term memory, demonstrated against a travel assistant built on Amazon Bedrock. The attack manipulates the agent’s session summarization process so malicious instructions become stored memory and persist across sessions. When the compromised memory is later injected into orchestration prompts, the agent can be coerced into unauthorized actions such as stealthy exfiltration. Unit 42 outlines layered mitigations including pre-processing prompts, Bedrock Guardrails, content filtering, URL allowlisting, and logging to reduce risk.

Code Assistant Risks: Indirect Prompt Injection and Misuse

🛡️ Unit 42 describes how IDE-integrated AI code assistants can be abused to insert backdoors, leak secrets, or produce harmful output by exploiting features like chat, auto-complete, and context attachment. The report highlights an indirect prompt injection vector where attackers contaminate public or third‑party data sources; when that data is attached as context, malicious instructions can hijack the assistant. It recommends reviewing generated code, controlling attached context, adopting standard LLM security practices, and contacting Unit 42 if compromise is suspected.