CVE-2020-27208: Nitrokey FIDO2 Firmware

Medium severity, CVSS 6.8. EPSS: 0.3% chance of exploitation in the next 30 days.

The flash read-out protection (RDP) level is not enforced during the device initialization phase of the SoloKeys Solo 4.0.0 & Somu and the Nitrokey FIDO2 token. This allows an adversary to downgrade the RDP level and access secrets such as private ECC keys from SRAM via the debug interface.

Affected products

• Nitrokey FIDO2 Firmware: affected versions not specified
• Solokeys Solo Firmware: version 4.0.0 only
• Solokeys Somu Firmware: affected versions not specified

Published 2021-05-21. Last modified 2026-06-17.