How severe is CVE-2021-42059?

CVE-2021-42059 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-42059 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42059?

CVE-2021-42059 primarily affects Insyde Insydeh2o. In total, 15 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-42059?

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

When was CVE-2021-42059 published?

CVE-2021-42059 was published on 2022-02-03 and last updated on 2026-06-17.

CVE-2021-42059

CVE-2021-42059 is a medium-severity vulnerability in Insyde Insydeh2o with a CVSS 3.x base score of 6.7. 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-787.

Key facts

Severity: Medium (CVSS 3.x base score 6.7)
CVSS v2: 7.2
EPSS exploit prediction: 0% (27th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Insyde Insydeh2o
Published: 2022-02-03
Last modified: 2026-06-17

Description

An issue was discovered in Insyde InsydeH2O Kernel 5.0 before 05.08.41, Kernel 5.1 before 05.16.41, Kernel 5.2 before 05.26.41, Kernel 5.3 before 05.35.41, and Kernel 5.4 before 05.42.20. A stack-based buffer overflow leads toarbitrary code execution in UEFI DisplayTypeDxe DXE driver.

Frequently asked questions

What is CVE-2021-42059?: An issue was discovered in Insyde InsydeH2O Kernel 5.0 before 05.08.41, Kernel 5.1 before 05.16.41, Kernel 5.2 before 05.26.41, Kernel 5.3 before 05.35.41, and Kernel 5.4 before 05.42.20. A stack-based buffer overflow leads toarbitrary code execution in UEFI DisplayTypeDxe DXE driver.
How severe is CVE-2021-42059?: CVE-2021-42059 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-42059 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42059?: CVE-2021-42059 primarily affects Insyde Insydeh2o. In total, 15 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-42059?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-42059 published?: CVE-2021-42059 was published on 2022-02-03 and last updated on 2026-06-17.

References

Affected products (15)

cpe:2.3:a:insyde:insydeh2o:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_field_pg_m5_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_field_pg_m6_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_ipc127e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_ipc227g_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_ipc277g_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_ipc327g_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_ipc377g_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_ipc427e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_ipc477e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_ipc627e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_ipc647e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_ipc677e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_ipc847e_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_itp1000_firmware:*:*:*:*:*:*:*:*

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