How severe is CVE-2021-29415?

CVE-2021-29415 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-29415 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-29415?

CVE-2021-29415 affects Nordicsemi Nrf52840 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-29415?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-29415 published?

CVE-2021-29415 was published on 2021-05-21 and last updated on 2026-06-17.

CVE-2021-29415

CVE-2021-29415 is a medium-severity vulnerability in Nordicsemi Nrf52840 Firmware with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-203.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 2.1
EPSS exploit prediction: 0% (19th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-203
Affected product: Nordicsemi Nrf52840 Firmware
Published: 2021-05-21
Last modified: 2026-06-17

Description

The elliptic curve cryptography (ECC) hardware accelerator, part of the ARM® TrustZone® CryptoCell 310, contained in the NordicSemiconductor nRF52840 through 2021-03-29 has a non-constant time ECDSA implemenation. This allows an adversary to recover the private ECC key used during an ECDSA operation.

Frequently asked questions

What is CVE-2021-29415?: The elliptic curve cryptography (ECC) hardware accelerator, part of the ARM® TrustZone® CryptoCell 310, contained in the NordicSemiconductor nRF52840 through 2021-03-29 has a non-constant time ECDSA implemenation. This allows an adversary to recover the private ECC key used during an ECDSA operation.
How severe is CVE-2021-29415?: CVE-2021-29415 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-29415 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-29415?: CVE-2021-29415 affects Nordicsemi Nrf52840 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-29415?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-29415 published?: CVE-2021-29415 was published on 2021-05-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:nordicsemi:nrf52840_firmware:*:*:*:*:*:*:*:*

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