How severe is CVE-2023-27373?

CVE-2023-27373 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 none, integrity high, and availability none.

Is CVE-2023-27373 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-27373?

CVE-2023-27373 primarily affects Insyde Insydeh2o. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-27373?

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

When was CVE-2023-27373 published?

CVE-2023-27373 was published on 2023-08-07 and last updated on 2026-06-17.

CVE-2023-27373

CVE-2023-27373 is a medium-severity vulnerability in Insyde Insydeh2o 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
EPSS exploit prediction: 0% (7th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Insyde Insydeh2o
Published: 2023-08-07
Last modified: 2026-06-17

Description

An issue was discovered in Insyde InsydeH2O with kernel 5.0 through 5.5. Due to insufficient input validation, an attacker can tamper with a runtime-accessible EFI variable to cause a dynamic BAR setting to overlap SMRAM.

Frequently asked questions

What is CVE-2023-27373?: An issue was discovered in Insyde InsydeH2O with kernel 5.0 through 5.5. Due to insufficient input validation, an attacker can tamper with a runtime-accessible EFI variable to cause a dynamic BAR setting to overlap SMRAM.
How severe is CVE-2023-27373?: CVE-2023-27373 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 none, integrity high, and availability none.
Is CVE-2023-27373 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-27373?: CVE-2023-27373 primarily affects Insyde Insydeh2o. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-27373?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-27373 published?: CVE-2023-27373 was published on 2023-08-07 and last updated on 2026-06-17.

References

https://www.insyde.com/security-pledge/SA-2023035

Affected products (6)

cpe:2.3:a:insyde:insydeh2o:5.0:*:*:*:*:*:*:*
cpe:2.3:a:insyde:insydeh2o:5.1:*:*:*:*:*:*:*
cpe:2.3:a:insyde:insydeh2o:5.2:*:*:*:*:*:*:*
cpe:2.3:a:insyde:insydeh2o:5.3:*:*:*:*:*:*:*
cpe:2.3:a:insyde:insydeh2o:5.4:*:*:*:*:*:*:*
cpe:2.3:a:insyde:insydeh2o:5.5:*:*:*:*:*:*:*

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