Researchers have identified a set of malicious Google Chrome extensions that abuse their granted permissions to hijack affiliate links, steal sensitive user data, and collect authentication tokens for OpenAI's ChatGPT service. A prominent example is the Amazon Ads Blocker extension, which claims to enhance user experience by removing sponsored content on Amazon but instead performs covert data theft and affiliate link manipulation. These extensions exploit the trust users place in browser add-ons, leveraging permissions to intercept web traffic and extract authentication tokens stored in browser sessions. The theft of ChatGPT tokens can allow attackers to impersonate users or access their AI interactions, potentially exposing sensitive or proprietary information. Affiliate link hijacking redirects legitimate referral commissions to attacker-controlled accounts, resulting in financial fraud. The threat does not require additional user authentication beyond installing the extension, and user interaction is minimal, increasing the risk of widespread compromise. Although no active exploits have been reported in the wild, the potential impact on confidentiality, integrity, and financial trust is substantial. The threat highlights the risks inherent in browser extension ecosystems, especially when extensions request broad permissions. Organizations relying on Chrome and ChatGPT services must be vigilant to prevent unauthorized access and data leakage through such extensions.

For European organizations, this threat poses significant risks to data confidentiality and financial integrity. The theft of ChatGPT authentication tokens could lead to unauthorized access to AI-driven workflows, exposing sensitive business communications and intellectual property. Affiliate link hijacking can result in financial losses and reputational damage, especially for companies involved in e-commerce or digital marketing. The widespread use of Google Chrome and increasing adoption of ChatGPT services in Europe amplify the potential attack surface. Compromise of employee browsers can lead to lateral movement or further exploitation within corporate networks. Additionally, regulatory implications under GDPR arise if personal or sensitive data is exfiltrated via these malicious extensions. The threat could disrupt business operations by undermining trust in digital tools and necessitating costly incident response and remediation efforts.

European organizations should implement strict browser extension policies, including whitelisting approved extensions and disabling installation of unverified add-ons. Employ enterprise management tools to enforce extension controls and monitor for unauthorized installations. Educate employees about the risks of installing extensions from untrusted sources and encourage regular audits of installed extensions. Use endpoint detection and response (EDR) solutions to identify suspicious browser behaviors indicative of token theft or affiliate link manipulation. Monitor network traffic for unusual redirects or data exfiltration patterns related to affiliate links. For ChatGPT users, enforce token management best practices, including regular token revocation and use of multi-factor authentication where possible. Collaborate with IT and security teams to promptly remove malicious extensions and conduct forensic analysis following detection. Stay updated with threat intelligence feeds to identify emerging malicious extensions and vulnerabilities in browser ecosystems.