TamperedChef: Malware Hidden in Productivity Apps Stealing Your Data

Attackers are always looking for new ways to exploit the trust you place in your digital tools. One of the latest campaigns makes this clear: TamperedChef hides inside seemingly harmless productivity apps—like calendars and image viewers—to infiltrate your systems, steal sensitive data, and remain undetected for weeks or even months.

At TecnetOne, we want you to understand what this threat means, how it works, and what you can do to protect your digital life and your business.

What Is TamperedChef and Why Is It So Dangerous?

TamperedChef is a cross-platform malware distributed under the guise of legitimate programs. Its creators have launched two main apps:

1. Calendaromatic.exe (masquerading as a calendar tool)

1. ImageLooker.exe (pretending to be an image viewer)

At first glance, these seem like useful programs. In reality, they’re trojans designed to steal your credentials, modify your browser’s settings, hijack your web traffic, and maintain remote access to your device.

Most alarmingly, they exploit your trust in digitally signed software. These apps were signed with certificates from real companies, giving them an air of legitimacy that fooled both users and many antivirus solutions.

How the Malware Is Distributed

TamperedChef’s distribution method is as sophisticated as the malware itself. Attackers use:

1. Self-extracting 7-Zip archives exploiting CVE-2025-0411 to bypass Windows protections like SmartScreen and “Mark of the Web.”

1. Malicious SEO and deceptive advertising, placing ads and manipulating search results to lure people seeking free productivity apps.

1. Suspicious repositories, uploading the apps to sites that look legitimate, with attractive download buttons and convincing descriptions.

In other words, the strategy is clear: exploit your search for free utilities so that you install the malware yourself.

Also of interest: How to Detect and Remove Spyware Apps on Android

A Technically Advanced Attack

TamperedChef goes beyond simply hiding malware in common apps. It shows a concerning level of engineering:

1. Use of NeutralinoJS
   These apps are built with this lightweight framework, allowing JavaScript to run as a desktop app. Attackers can directly interact with system APIs while you believe you’re using a legitimate program.

1. Evasion via Unicode Homoglyphs
   The malware encodes its malicious payloads using Unicode characters that look identical to normal ones, tricking detection systems scanning for suspicious strings.

1. Covert Execution Channels
   By decoding these hidden payloads and executing them within NeutralinoJS, attackers create a stealthy channel that bypasses traditional antivirus tools.

1. Guaranteed Persistence
   TamperedChef ensures it stays on your system by creating scheduled tasks and modifying the registry with flags like --install, --enableupdate, and --fullupdate.

1. Constant C2 Communication
   Once inside, it connects to remote servers like calendaromatic[.]com or movementxview[.]com, allowing attackers to send commands and continuously exfiltrate data.

What TamperedChef Steals

This campaign’s impact goes far beyond a few compromised files. The malware aims for full control of your digital environment:

1. Credentials stored in browsers (Chrome, Safari, and others)

1. Data from extensions, including cryptocurrency wallets

1. Clipboard content, including seed phrases and private keys

1. Cookies and local databases, enabling attackers to hijack active sessions

1. Screenshots, giving visual evidence of what’s on your device

If you’re a developer or work in finance, TamperedChef can, within minutes, drain your crypto wallets, access your corporate email, and leak your company’s data.

Similar titles: Vulnerability in macOS Sploitlight Leaks Apple Intelligence Data

What Makes TamperedChef Different

While other infostealers target macOS, Windows, and Linux, TamperedChef stands out by:

1. Impersonating signed apps using valid digital certificates to bypass basic defenses

1. Targeting Safari, less common in the malware ecosystem, where Chrome is usually the main focus

1. Acting persistently and discreetly without affecting system performance immediately, delaying detection

How to Protect Yourself

At TecnetOne, we recommend a layered security approach to minimize the risk of threats like TamperedChef:

1. Download software only from official sources. If an app isn’t on the provider’s official website, be suspicious.

1. Keep your systems updated. Patches like those addressing CVE-2025-0411 are vital.

1. Enable advanced security solutions. Don’t rely solely on basic antivirus; behavioral detection and traffic analysis tools are key.

1. Monitor browser extensions. Remove unused ones and review their permissions.

1. Train your team on phishing and suspicious downloads, as social engineering remains the most effective attack vector.

1. Use password managers and MFA. Even if one credential is stolen, a second layer of protection can stop the attack.

The Role of Awareness

Ultimately, this type of malware exploits a combination of trust and carelessness. Most victims believe they’re downloading something legitimate—that’s where attackers succeed.

At TecnetOne, we know cybersecurity isn’t just about technology; it’s also about organizational culture. If you and your team routinely verify the source of software and treat suspicious links with caution, you drastically reduce the scope of threats like TamperedChef.

Conclusion

TamperedChef represents a clear evolution in how attackers blend advanced evasion techniques, vulnerability exploitation, and impersonation of legitimate software to steal valuable information.

The lesson is clear: having an antivirus installed isn’t enough. You need comprehensive strategies combining technology, best practices, and specialized security services.

At TecnetOne, we’re committed to helping you protect your digital environment from threats like TamperedChef, offering advanced monitoring, incident response, and security audits to detect these anomalies before it’s too late.