AI Prompt Injection and Data Leakage Vulnerabilities in OpenAI's ChatGPT and Atlas Browser
Tenable Research has identified seven novel vulnerabilities and attack techniques in OpenAI's ChatGPT, including indirect prompt injections, exfiltration of user data, and bypasses of safety mechanisms in the latest GPT-5 model. These vulnerabilities allow attackers to manipulate the large language model (LLM) through crafted inputs, potentially leading to the theft of private information from user memories and chat histories, even when users simply interact with ChatGPT. The research highlights that hundreds of millions of users could be at risk, as attackers can exploit these weaknesses to bypass safeguards and extract sensitive data without user awareness.
The release of OpenAI's ChatGPT Atlas, an AI-powered browser that remembers user activities and acts autonomously, further amplifies these concerns. Security experts warn that features such as persistent memory and autonomous actions increase the attack surface, making the browser susceptible to prompt injection and other AI-specific vulnerabilities. The implications for enterprise security and privacy are significant, as these AI-driven tools become more integrated into business processes, necessitating new approaches to identity management, access controls, and oversight to mitigate the risks posed by advanced AI-enabled attacks.
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Researchers disclose HackedGPT AI data-leakage vulnerabilities
Tenable published research on novel 'HackedGPT' vulnerabilities that could enable private data leakage in AI systems. The disclosure highlighted new attack paths affecting AI applications and raised concerns about protecting sensitive information in generative AI environments.
OpenAI launches ChatGPT Atlas
OpenAI introduced ChatGPT Atlas, a new ChatGPT-related offering that prompted cybersecurity and privacy analysis about its potential risks and implications. The launch became the basis for subsequent reporting and commentary in early November 2025.
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HackedGPT: Novel AI Vulnerabilities Open the Door for Private Data Leakage
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Prompt Injection and Browser-Based AI Security Risks
The launch of ChatGPT Atlas, an AI-powered web browser with agentic capabilities, has raised significant concerns about prompt injection attacks. As browsers become more integrated with large language models (LLMs), attackers can exploit both direct and indirect prompt injection techniques to manipulate AI agents, potentially causing them to divulge sensitive information or perform unintended actions. The accessibility of such agentic browsers, combined with their ability to automate complex tasks, amplifies the risk landscape for organizations adopting these technologies. Security experts warn that the browser now represents a critical control point for AI security, as it serves as the main interface between users and generative AI systems. The rapid increase in GenAI browser traffic has led to a surge in data security incidents, including inadvertent exposure of confidential information through LLM prompts. Traditional network security measures are often insufficient to address these browser-borne threats, making it imperative for organizations to reassess their security strategies and implement controls specifically designed to mitigate risks associated with AI-powered browsers and prompt injection attacks.
Mar 21, 2026
Prompt Injection and Persistent Memory Exploits in AI-Powered Browsers
Researchers have identified critical security vulnerabilities in several AI-powered browsers, including OpenAI's Atlas and other emerging platforms such as Comet and Fellou. These browsers, which allow AI agents to perform actions on behalf of users, are susceptible to prompt injection attacks—where hidden or malicious instructions embedded in web content are executed by the AI. In documented cases, attackers were able to hide commands in web pages or images, leading the browser to perform unauthorized actions such as extracting email subject lines and exfiltrating data to attacker-controlled sites, all without user confirmation. A particularly severe exploit targets the persistent memory feature of the ChatGPT Atlas browser, introduced by OpenAI to personalize user experiences. By chaining a cross-site request forgery (CSRF) vulnerability with a memory write, attackers can inject malicious instructions that persist across sessions, devices, and even different browsers. This allows for ongoing compromise, including privilege escalation, malware deployment, and account takeover, unless users manually clear the tainted memory. The persistence and stealth of these attacks significantly elevate the risk profile for users of AI-enabled browsers, highlighting the urgent need for robust security controls and user awareness around prompt injection threats.
Apr 9, 2026
OpenAI's Ongoing Defense Against Prompt Injection Attacks in ChatGPT Atlas
OpenAI has implemented an automated attacker system to proactively test and strengthen the security of ChatGPT Atlas, its agentic web browser, against prompt injection attacks. These attacks involve embedding malicious instructions into content that the AI agent processes, potentially causing it to act against the user's interests. The company acknowledges that the very features making agentic browsers powerful also introduce persistent vulnerabilities, and that complete protection from prompt injection is unlikely. OpenAI's approach leverages AI-driven red teaming to rapidly identify and address new attack vectors, aiming to stay ahead of evolving threats. A recent security update to Atlas was prompted by the internal discovery of a new class of prompt injection attacks using this automated red-teaming system. The attack surface for browser agents is broad, as they can interact with untrusted content from emails, documents, social media, and web pages, increasing the risk of harmful actions such as forwarding sensitive information or altering cloud files. OpenAI emphasizes that defending against prompt injection will be a continuous effort, likening it to an arms race similar to combating online scams, and stresses the importance of a rapid response loop to reduce real-world risks over time.
Mar 21, 2026