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TamperedChef Malware Campaign Targets Users via Fake PDF Editors

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📰 2 unique sources, 2 articles

Summary

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A cybercrime campaign using malvertising to distribute a new information stealer called TamperedChef has been discovered. The malware is disguised as a fake PDF editor, AppSuite PDF Editor, and is designed to steal sensitive data, including credentials and web cookies. The campaign began on June 26, 2025, with malicious capabilities activated on August 21, 2025. The malware operates as a backdoor, supporting various features for data exfiltration and system manipulation. The campaign involves multiple fraudulent websites promoting the PDF editor, which, once installed, makes covert requests to an external server to drop the PDF editor program and set up persistence on the host. The malware gathers information about installed security products and attempts to terminate web browsers to access sensitive data. The campaign includes more than 50 domains and apps signed with fraudulent certificates from at least four companies. The threat actor has been active since at least August 2024, promoting other tools like OneStart and Epibrowser, which can turn hosts into residential proxies.

Timeline

  1. 30.08.2025 19:22 📰 1 articles · ⏱ 17d ago

    TamperedChef Campaign Expands with Multiple Apps and Proxy Networks

    The campaign involves more than 50 domains and apps signed with fraudulent certificates from at least four companies. The threat actor has been active since at least August 2024, promoting other tools like OneStart and Epibrowser. These tools can turn hosts into residential proxies, and the campaign includes apps that can download each other, some tricking users into enrolling their systems into residential proxies. The operation involves more apps, some of which are not yet weaponized but capable of distributing malware or executing commands surreptitiously on the system.

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  2. 29.08.2025 07:17 📰 2 articles · ⏱ 18d ago

    TamperedChef Malware Campaign Begins Distribution via Fake PDF Editors

    The campaign involves more than 50 domains hosting deceptive apps. The apps are signed with fraudulent certificates issued by at least four different companies, including ECHO Infini SDN BHD, GLINT By J SDN. BHD, and SUMMIT NEXUS Holdings LLC. The threat actor has been active since at least August 2024, promoting other tools like OneStart and Epibrowser, which can turn hosts into residential proxies. The campaign includes apps that can download each other, some tricking users into enrolling their systems into residential proxies.

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