AI Agent Tool Invocation - AI Security Technique

Researchers at HiddenLayer demonstrated how a webpage can embed an indirect prompt injection that causes OpenClaw to silently execute a malicious script. Once executed, the script plants persistent malicious instructions into future system prompts, allowing the attacker to issue new commands, turning OpenClaw into a command and control agent.

What makes this attack unique is that, through a simple indirect prompt injection attack into an agentic lifecycle, untrusted content can be used to spoof the model’s control scheme and induce unapproved tool invocation for execution. Through this single inject, an LLM can become a persistent, automated command & control implant.

A security researcher demonstrated a proof-of-concept supply chain attack using a poisoned ClawdBot Skill shared on ClawdHub, a Skill registry for agents. The poisoned Skill contained a prompt injection that caused ClawdBot to execute a shell command that reached the researcher's server. Although the researcher here used this access simply to warn users about the danger, they could have instead delivered a malicious payload and compromised the user's system. The security researcher recorded 16 different users who downloaded and executed the poisoned Skill in the first 8 hours of it being published on ClawdHub.

A security researcher identified hundreds of exposed ClawdBot control interfaces on the public internet. ClawdBot (now OpenClaw) “is a personal AI assistant you run on your own devices. It answers you on the channels you already use … , plus extension channels. … It can speak and listen on macOS/iOS/Android, and can render a live Canvas you control.”^[1] The researcher was able to access credentials to a variety of connected applications via ClawdBot’s configuration file. They were also able to invoke ClawdBot’s skills by prompting it via the chat interface, leading to root access in the container.

The researcher searched Shodan^[2] to identify Clawdbot instances exposed on the public internet, some without authentication enabled. The researcher demonstrated that the ClawdBot’s authentication mechanism could be bypassed due to a proxy misconfiguration.

With access to ClawdBot’s control interface, they were then able to access ClawdBot’s configuration, which contained credentials to a variety of other services. Across various exposed instances of ClawdBot, they identified Anthropic API Keys, Telegram Bot Tokens, Slack Oauth Credentials, and Signal Device Linking URIs. The researcher prompted ClawdBot directly via the chat interface, which led to exposure of its system prompt. They were also able to get ClawdBot to execute commands via it’s bash skill, which at least in once instance led to root access in the ClawdBot container.

The researcher noted a broad range of other impacts they could have had with this level of access, including:

• Manipulation of user chat history with the ClawdBot AI agent
• Exfiltration of conversation histories of any connected messaging services
• Impersonation of users by sending messages on their behalf via connected messaging services

References

1. [1] https://github.com/openclaw/openclaw
2. [2] https://www.shodan.io/search?query=Clawdbot+Control

The Backslash Security Research Team demonstrated that a Model Context Protocol (MCP) tool can be used as a vector for an indirect prompt injection attack on Cursor, potentially leading to the execution of malicious shell commands.

The Backslash Security Research Team created a proof-of-concept MCP server capable of scraping webpages. When a user asks Cursor to use the tool to scrape a site containing a malicious prompt, the prompt is injected into Cursor’s context. The prompt instructs Cursor to execute a shell command to exfiltrate the victim’s AI agent configuration files containing credentials. Cursor does prompt the user before executing the malicious command, potentially mitigating the attack.