Hardware Security Assessment for Smart Home Appliances

A German smart kitchen appliance manufacturer running a recipe-subscription model asked Payatu to protect its proprietary recipes and firmware from extraction. Testing pulled hardcoded encryption keys straight from the hardware and used a malicious firmware zip file to escalate to root privileges, all within four weeks.

Hardware Security Assessment, Firmware Security Assessment

At a glance

INDUSTRY

Consumer IoT / Smart Kitchen Appliances

CLIENT PROFILE

A German company and one of its largest smart kitchen appliance manufacturers

SERVICES

Hardware Security Assessment, Firmware Security Assessment

ENGAGEMENT

Four-week assessment of a subscription-based smart food processor

Key Takeaways

Client – A German company and one of the country's largest smart kitchen appliance manufacturers, running a subscription model built on proprietary, cloud-delivered recipes.

Problem – Users could try to extract proprietary recipes or bypass the subscription model, and competitors could steal the device's design, so the client needed its intellectual property protected at the hardware and firmware level.

What Payatu did – Extracted hardcoded encryption keys from the device hardware and exploited the firmware upgrade process, delivered via an external USB zip file, to escalate to root privileges.

Outcome – Helped the client mitigate the risk of IP theft, subscription bypass and financial loss within a four-week assessment.

the challenge

Why the client called us in

The client's food processor runs on a subscription model: users register on the company's cloud system and download proprietary, predesigned recipes to the device rather than sourcing their own. That model only works if the recipes and the firmware behind it stay protected, from users trying to extract recipes for free, users bypassing the subscription entirely, or competitors cloning the device's design. The client brought in Payatu to assess the device's security before those risks materialized.

Determine whether proprietary recipes could be extracted from the device
Test whether the subscription model could be bypassed
Assess whether the device's design and firmware were exposed to cloning

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scope of engagement

What was in scope

Hardware and encryption key extraction assessment
Firmware upgrade mechanism assessment

Our Approach

How Payatu ran the engagement

01

Hardware Assessment

Extracted encryption keys hardcoded on the device, which unlocked access to the device's intellectual property, including subscribed recipes.

02

Firmware Upgrade Exploitation

Replaced the zip file the device used to download firmware onto external USB storage with a malicious zip file, executing code and escalating privileges to gain root access to the device.

Key findings

What we found

Hardcoded Encryption Keys

Encryption keys hardcoded on the device could be extracted, unlocking access to the device's intellectual property, including subscription-only recipes.

Insecure Firmware Upgrade

The firmware upgrade process downloaded an unauthenticated zip file to external USB storage; replacing it with a malicious zip file allowed code execution and privilege escalation to root.

the outcome

Results and Impact

With Payatu's four-week assessment, the client mitigated the risk of IP theft and the recurring revenue loss that comes from subscription bypass, closing both issues before they reached its customer base.