How severe is CVE-2020-5953?

CVE-2020-5953 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over local access with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-5953 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-5953?

CVE-2020-5953 primarily affects Insyde Insydeh2o. In total, 22 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-5953?

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-2020-5953 published?

CVE-2020-5953 was published on 2022-02-03 and last updated on 2026-06-17.

CVE-2020-5953

CVE-2020-5953 is a high-severity vulnerability in Insyde Insydeh2o with a CVSS 3.x base score of 7.5. 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 7.5)
CVSS v2: 6.9
EPSS exploit prediction: 0% (20th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Insyde Insydeh2o
Published: 2022-02-03
Last modified: 2026-06-17

Description

A vulnerability exists in System Management Interrupt (SWSMI) handler of InsydeH2O UEFI Firmware code located in SWSMI handler that dereferences gRT (EFI_RUNTIME_SERVICES) pointer to call a GetVariable service, which is located outside of SMRAM. This can result in code execution in SMM (escalating privilege from ring 0 to ring -2).

Frequently asked questions

What is CVE-2020-5953?: A vulnerability exists in System Management Interrupt (SWSMI) handler of InsydeH2O UEFI Firmware code located in SWSMI handler that dereferences gRT (EFI_RUNTIME_SERVICES) pointer to call a GetVariable service, which is located outside of SMRAM. This can result in code execution in SMM (escalating privilege from ring 0 to ring -2).
How severe is CVE-2020-5953?: CVE-2020-5953 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over local access with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-5953 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (20th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-5953?: CVE-2020-5953 primarily affects Insyde Insydeh2o. In total, 22 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-5953?: 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-2020-5953 published?: CVE-2020-5953 was published on 2022-02-03 and last updated on 2026-06-17.

References

Affected products (22)

cpe:2.3:a:insyde:insydeh2o:5.12.09.0074:*:*:*:*:*:*:*
cpe:2.3:a:insyde:insydeh2o:5.23.04.0045:*:*:*:*:*:*:*
cpe:2.3:a:insyde:insydeh2o:5.23.45.0023:*:*:*:*:*:*:*
cpe:2.3:a:insyde:insydeh2o:5.33.15.0034:*:*:*:*:*:*:*
cpe:2.3:a:insyde:insydeh2o:5.34.03.0029:*:*:*:*:*:*:*
cpe:2.3:a:insyde:insydeh2o:5.42.03.0010:*:*:*:*:*:*:*
cpe:2.3:o:siemens:ruggedcom_ape1808_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_itp1000_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:siemens:simatic_ipc477e_pro_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_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_field_pg_m5_firmware:-:*:*:*:*:*:*:*

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