Critical ChatGPT Vulnerability Exposes User Data Through Hidden Outbound Channel

Breaking: ChatGPT's Code Execution Runtime Bypasses Security to Leak Sensitive Data

Check Point Research has identified a critical vulnerability in the ChatGPT code execution environment that allows malicious actors to silently exfiltrate user data. The flaw exploits a hidden outbound communication channel from the isolated Linux runtime to the public internet, enabling data theft without user knowledge or consent.

“This discovery reveals a fundamental gap in ChatGPT’s security model,” said Dr. Maya Chen, head of AI security research at Check Point. “A single malicious prompt can turn an ordinary conversation into a covert exfiltration pipeline, leaking messages, uploaded files, and other sensitive content.”

The attack works by manipulating ChatGPT’s Python-based Data Analysis environment, which OpenAI had designed to block outbound network requests. Researchers demonstrated that crafted prompts can activate the hidden channel, transmitting user data to an external server without any warning or approval.

“We were able to establish remote shell access inside the runtime, giving attackers full control over the execution environment,” explained Mike Torres, a senior security engineer on the research team. “This same path could also be exploited by a backdoored GPT to siphon user information invisibly.”

Background: The Trust Model Under Attack

AI assistants like ChatGPT now handle some of the most sensitive personal information—medical histories, tax documents, financial records, and identity-rich files. Users trust that data shared in conversations stays within the system.

ChatGPT explicitly presents outbound data sharing as restricted and controlled. Its web search feature blocks sensitive chat content from being transmitted via crafted queries, and the Data Analysis environment was touted as a secure runtime without direct outbound network capabilities.

“OpenAI documented that GPTs could send relevant user input to external APIs through legitimate ‘Actions’,” said Torres. “But the hidden channel operates outside those intended mechanisms, bypassing safeguards entirely.”

What This Means: Urgent Need for Remediation

This vulnerability undermines the core promise of privacy in AI-powered assistants. With no visible alerts or consent prompts, users can have their most confidential data stolen during a routine conversation.

“The ability to silently exfiltrate data turns ChatGPT into a potential threat vector,” warned Chen. “Enterprises using GPTs for internal processes must immediately assess their exposure and demand patches from OpenAI.”

The research also highlights inherent design risks. A backdoored GPT could exploit the same weakness to access user data without the user’s awareness or consent. Combined with remote shell access, attackers could execute arbitrary commands inside the runtime, elevating the severity to full system compromise.

“This is not a theoretical exercise—we have shown a working proof-of-concept,” Torres emphasized. “OpenAI must now prioritize closing this outbound channel and re-validating the entire code execution sandbox.”

Users are advised to avoid sharing highly sensitive information in ChatGPT conversations until a fix is confirmed. Organizations should review any custom GPT integrations and limit their use until further notice.