How severe is CVE-2021-27138?

CVE-2021-27138 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-27138 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27138?

CVE-2021-27138 primarily affects Denx U-boot. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-27138?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-27138 published?

CVE-2021-27138 was published on 2021-02-17 and last updated on 2026-06-17.

CVE-2021-27138

CVE-2021-27138 is a high-severity vulnerability in Denx U-boot with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 6.8
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Denx U-boot
Published: 2021-02-17
Last modified: 2026-06-17

Description

The boot loader in Das U-Boot before 2021.04-rc2 mishandles use of unit addresses in a FIT.

Frequently asked questions

What is CVE-2021-27138?: The boot loader in Das U-Boot before 2021.04-rc2 mishandles use of unit addresses in a FIT.
How severe is CVE-2021-27138?: CVE-2021-27138 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-27138 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27138?: CVE-2021-27138 primarily affects Denx U-boot. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-27138?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-27138 published?: CVE-2021-27138 was published on 2021-02-17 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:denx:u-boot:*:*:*:*:*:*:*:*
cpe:2.3:a:denx:u-boot:2021.04:rc1:*:*:*:*:*:*

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