CVE-2020-27211

Nordic Semiconductor nRF52840 devices through 2020-10-19 have improper protection against physical side channels. The flash read-out protection (APPROTECT) can be bypassed by injecting a fault during the boot phase.

Published: 2021-05-21 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-27211 is rated Low Risk (29.7/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.28%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2020-27211

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.04% 0.28% +0.23%
2 2026-02-01 0.08% 0.04% -0.04%
3 2025-03-30 — 0.08% —

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-27211

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.7 3.1 MEDIUM
CVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N Click to expand
Attack vector (AV:P)
Hands-on access—USB, keyboard, opening the case—not something you do purely over the wire.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 0.5 5.2 [email protected]
3.3 2.0 LOW
AV:L/AC:M/Au:N/C:P/I:P/A:N Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 3.4 4.9 [email protected]

Weakness enumeration for CVE-2020-27211

Affected software / configurations for CVE-2020-27211

Vendor Product Version Raw CPE
nordicsemi nrf52840_firmware <= 2020-10-19 cpe:2.3:o:nordicsemi:nrf52840_firmware:*:*:*:*:*:*:*:*

References for CVE-2020-27211

cvelogic Threat Intelligence