HOMEVULNERABILITIESCVE-2020-27208
MEDIUM

CVE-2020-27208

CWE-326Published: May 21, 2021· Updated: Jun 17, 2026

6.8
CVSS v3.1

Official Description

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.

NVD Source

Technical Analysis

CVE-2020-27208 requires local access, meaning attackers must already have a foothold on the target system.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 6.8.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorPhysical
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected Vendors & Products

nitrokey2 product(s)
fido2 firmwarefido2
solokeys4 product(s)
solo firmwaresolosomu firmwaresomu
Source: NVD CPE · 6 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

PATCHhttps://github.com/solokeys/solo/commit/a9c02cd354f34b48195a342c7f524abdef5cbcec
PATCHhttps://github.com/solokeys/solo/commit/a9c02cd354f34b48195a342c7f524abdef5cbcec
ADVISORYhttps://eprint.iacr.org/2021/640
ADVISORYhttps://www.aisec.fraunhofer.de/de/das-institut/wissenschaftliche-exzellenz/security-and-trust-in-open-source-security-tokens.html
ADVISORYhttps://www.aisec.fraunhofer.de/en/FirmwareProtection.html
ADVISORYhttps://eprint.iacr.org/2021/640
ADVISORYhttps://www.aisec.fraunhofer.de/de/das-institut/wissenschaftliche-exzellenz/security-and-trust-in-open-source-security-tokens.html
ADVISORYhttps://www.aisec.fraunhofer.de/en/FirmwareProtection.html

All References (12)

→
https://eprint.iacr.org/2021/640Third Party Advisory
→
https://github.com/solokeys/solo/commit/a9c02cd354f34b48195a342c7f524abdef5cbcecPatch · Third Party Advisory
→
https://solokeys.comProduct
→
https://twitter.com/SoloKeysSecProduct
→
https://www.aisec.fraunhofer.de/de/das-institut/wissenschaftliche-exzellenz/security-and-trust-in-open-source-security-tokens.htmlThird Party Advisory
→
https://www.aisec.fraunhofer.de/en/FirmwareProtection.htmlExploit · Third Party Advisory
→
https://eprint.iacr.org/2021/640Third Party Advisory
→
https://github.com/solokeys/solo/commit/a9c02cd354f34b48195a342c7f524abdef5cbcecPatch · Third Party Advisory
→
https://solokeys.comProduct
→
https://twitter.com/SoloKeysSecProduct
→
https://www.aisec.fraunhofer.de/de/das-institut/wissenschaftliche-exzellenz/security-and-trust-in-open-source-security-tokens.htmlThird Party Advisory
→
https://www.aisec.fraunhofer.de/en/FirmwareProtection.htmlExploit · Third Party Advisory

Quick Facts

CVE IDCVE-2020-27208
CVSS Score6.8 / 10
SeverityMEDIUM
WeaknessCWE-326
CISA KEVNo
Affected2 vendor(s)
PublishedMay 21, 2021

Related CVEs (CWE-326)

CVE-2020-6966
10.0
CVE-2014-9199
10.0
CVE-2026-44523
10.0
CVE-2018-7242
9.8
CVE-2022-36555
9.8
CVE-2025-12478
9.8

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2020-27208 in threat intel feeds
  • →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.
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