Nest Learning Thermostat (4th Gen)（G4CVZ）

Nest Learning Thermostat (4th Gen)（G4CVZ）
Security Grade A- Calculator v	Google Nest Learning Thermostat (4th Generation) Brand: Nest / Google (Parent: Alphabet Inc.) Category: Smart Thermostat / IoT Climate Device • Model / Gen: 4th Generation G4CVZ Release Date: 2024-08-01 • Status: In sale Classification Date: • Official Website

Security Evaluation

1. Device Security

Criterion	Value	Proof	Comment
Known hardware tampering	Rare	[[1](https://store.google.com) 🔗 Proof]	Hardware modification uncommon
Known vulnerabilities	Rare	[[2](https://support.google.com/googlenest) 🔗 Proof]	Few public CVEs; Google pushes regular OTA patches
Prior attacks	Rare	[[3](https://store.google.com) 🔗 Proof]	No widespread mass attacks targeting 4th gen
Updatability	Very common	[[4](https://support.google.com/googlenest) 🔗 Proof]	Automatic OTA firmware updates
Category Score	Score: 2 / 3

2. System Security

Criterion	Value	Proof	Comment
Authentication with other systems	Partial	[[5](https://store.google.com) 🔗 Proof]	Integrates with Google Assistant, Google Home ecosystem
Communications	Encrypted with up-to-date encryption	🔗 Proof	TLS 1.3 and AES encryption for cloud communication
Storage	Encrypted with up-to-date encryption	🔗 Proof	Usage/history data encrypted at rest in Google cloud
Category Score	Score: 2 / 3

3. User Authentication

Criterion	Value	Proof	Comment
Account management	Full	🔗 Proof	Google account management, home sharing
Authentication	Secure	🔗 Proof	Google account login + supports 2FA
Brute-force protection	Exist	🔗 Proof	Google account rate limiting / lockout
Event logging	Access event logged	🔗 Proof	Logs logins, temperature schedule, occupancy events
Passwords	Require change after setup with complexity requirements	🔗 Proof	Google enforces strong password rules
Category Score	Score: 1 / 3

Technical Specifications

Property	Details
Operating System & App	Nest embedded OS (Companion App: Google Home / Nest App)
Hardware (CPU / GPU)	CPU: ARM embedded processor • GPU: No dedicated GPU
Memory & Storage	Memory: 512 MB RAM • Storage: 4 GB flash
Power, Battery & Charging	Battery: Internal rechargeable battery, charged via HVAC wiring • Power: HVAC 24V AC / USB-C backup charging • Charging: USB-C backup charging
Display & Camera	Display: Round colour LCD • Camera: No camera
Sound & Connectivity	Sound: Small speaker for status alerts • Connectivity: Wi‑Fi 2.4GHz / 5GHz, Bluetooth
Physical (Dimensions & Mass)	Dimensions: Φ90 mm × 22 mm • Mass: 214 g

4th-gen Nest Learning Thermostat learns user temperature preferences and tracks occupancy/schedule data. It has no camera, reducing visual privacy risk, but activity data is sent to Google cloud. Receives regular OTA security updates.