This week’s Department of Know is hosted by Rich Stroffolino, with guests Jonathan Waldrop, CISO, Acoustic, and Jason Elrod, CISO, MultiCare Health System.
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In this week’s cybersecurity news…
Google Chrome installs 4GB AI model on devices
Computer scientist and lawyer Alexander Hanff reports that recent versions of Google Chrome automatically download a roughly 4GB Gemini Nano AI model to user devices without explicit consent when default AI features are enabled. He says the file installs silently, and can be re-downloaded after deletion. Hanff argues the behavior may violate privacy laws, cause increased power usage, and calls for an opt-in prompt.
New PCPJack worm steals credentials, cleans TeamPCP infections
A new malware framework called PCPJack is “stealing credentials from exposed cloud infrastructure while actively removing TeamPCP’s access to the systems.” It targets services such as Docker, Kubernetes, Redis, MongoDB, RayML, and vulnerable web applications, by moving laterally on the network. According to SentinelLabs, PCPJack is designed for large-scale credential theft in order to leverage financial fraud, spam operations, credential resale, or extortion. SentinelLabs also believes that PCPJack may have been developed by a former TeamPCP affiliate or member who started their own operation.
Nearly every Linux system built since 2017 vulnerable to ‘Copy Fail’ flaw
Security researchers at Theori are informing admins of a newly discovered security flaw that has been hiding in the Linux operating system since 2017. Named “Copy Fail,” this uses an AI-powered scanning tool called Xint Code. It “allows anyone with a basic account on an affected computer to seize full administrative control. It also works as an escape route from cloud containers, meaning a compromised application running inside a supposedly isolated environment can break out and take control of the entire host server.” It “affects every major Linux distribution released since 2017. Theori said “the flaw resulted from three separate, individually unremarkable changes to the Linux kernel.. and no one recognized the danger created by their combination for nearly a decade.
Every Yarbo lawnmower is hacked
Security researcher Andreas Makris disclosed that every Yarbo lawnmower is essentially a Linux computer whose root password is reset to a known stock value with each firmware update. Makris was able to vibe code a map of all mower locations, remotely control them, and get passwords for the networks they were on, and directly disregard user commands. The company had no bug bounty or channel to report bugs, and when trying to contact customer service was told this was by design so Yarbo could diagnose issues.
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The AI “Transformation Paradox”
Microsoft released its 2026 Work Trend Index report. One of the top-level findings is that 65% of workers fear falling behind if they don’t adapt to AI, but at the same time, 45% of workers feel safer focusing on current workflows than redesigning them for AI. Only 26% of respondents said their leadership is consistently aligned on AI, opening the door to potential Shadow AI proliferation. 16% of respondents were identified as “Frontier Professionals,” those who use multi-agent systems to rethink workflows. The biggest use case for AI was analysis and reasoning, used in 49% of chats. Interaction accounted for 19%, producing work 17%, and gathering information 15%.
Everyone is trying to ride the “patch wave”
The chief technology officer at the National Cyber Security Centre (NCSC), Ollie Whitehouse, said in a blog post, the use of AI tools “by sufficiently skilled and knowledgeable individuals” is increasing the likelihood that vulnerabilities will be identified and exploited at scale. He encouraged all organizations to prepare now for when a ‘patch wave’ arrives.
We’re already seeing the economics of this “patch wave” playing out. Google revamped its Vulnerability Reward Programs (VRP) for Android and Chrome. Android secure enclave exploits are getting a bump in bounties, but Chrome exploits are getting cut to up to a tenth of their former payouts. The idea is “to incentivize actionable reports, vulnerability submissions that include concrete proof, feasible exploit demonstrations, and ideally, suggested fixes.”
A tale of two critical infrastructure attacks
Taiwanese authorities arrested a 23-year-old student for interfering with the TETRA communications system used by the country’s high-speed rail network. The suspect allegedly used a software-defined radio to send a “General Alarm” signal that triggered emergency braking on nearby trains. This resulted in four trains being halted for 48 minutes on April 5th. The system’s verification keys hadn’t been refreshed in 19 years and used known broken encryption.
Then Poland’s domestic intelligence service said, “attackers breached water treatment facilities in five towns in 2025, in some cases gaining access to industrial control systems that could have disrupted water supplies.” The country’s Internal Security ABW said water treatment stations in six towns were targeted, with attackers, gaining access in some cases to industrial control systems, posing “a direct risk” to the continuity of water supply operations.