Yubico YubiKey 5 Series

Yubico YubiKey 5 Series
Security Grade B Calculator v1	YubiKey 5 Series (e.g., YubiKey 5C NFC) Brand: Yubico (Parent: Yubico AB) Category: Hardware Authentication Token / Security Key • Model / Gen: 5th Generation YubiKey 5C, 5C NFC, 5Ci, 5 NFC, etc. Release Date: 2018-09-01 • Status: In sale Classification Date: 2025-10-09 • Official Website

Security Evaluation

1. Device Security

Criterion	Value	Proof	Comment
Known hardware tampering	None	—
Known vulnerabilities	None	—
Prior attacks	None	—
Updatability	None	—
Category Score	Score: 2 / 3

2. System Security

Criterion	Value	Proof	Comment
Authentication with other systems	Full	—
Communications	Encrypted with up-to-date encryption	—
Storage	Encrypted with up-to-date encryption	—
Category Score	Score: 1 / 3

3. User Authentication

Criterion	Value	Proof	Comment
Account management	Absent	—
Authentication	Secure	—
Brute-force protection	Exist	—
Event logging	Absent	—
Passwords	Default/Common/Easy to guess	—
Category Score	Score: 3 / 3

Technical Specifications

Property	Details
Operating System & App	Proprietary Firmware (Companion App: Yubico Manager (for configuration))
Hardware (CPU / GPU)	CPU: Secure Element (Yubico Proprietary) • GPU: N/A
Memory & Storage	Memory: Limited onboard memory for configurations and secrets • Storage: Secure NVM (Non-Volatile Memory) for cryptographic keys
Power, Battery & Charging	Battery: N/A (Passive device, powered by host) • Power: USB-C / NFC / Lightning (depending on model) • Charging: N/A
Display & Camera	Display: N/A • Camera: N/A
Sound & Connectivity	Sound: N/A • Connectivity: USB-C, USB-A, Lightning, NFC (varies by model)
Physical (Dimensions & Mass)	Dimensions: Varies by model (e.g., 5C: 47mm x 15mm x 4.4mm) • Mass: Approx. 4.5g