How severe is CVE-2018-8435?

CVE-2018-8435 has a CVSS 3.x base score of 4.2, rated medium severity. It is exploitable over an adjacent network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2018-8435 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-8435?

CVE-2018-8435 primarily affects Microsoft Windows 10. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-8435?

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

When was CVE-2018-8435 published?

CVE-2018-8435 was published on 2018-09-13 and last updated on 2026-06-17.

CVE-2018-8435

CVE-2018-8435 is a medium-severity vulnerability in Microsoft Windows 10 with a CVSS 3.x base score of 4.2. 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-331.

Key facts

Severity: Medium (CVSS 3.x base score 4.2)
CVSS v2: 2.3
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-331
Affected product: Microsoft Windows 10
Published: 2018-09-13
Last modified: 2026-06-17

Description

A security feature bypass vulnerability exists when Windows Hyper-V BIOS loader fails to provide a high-entropy source, aka "Windows Hyper-V Security Feature Bypass Vulnerability." This affects Windows Server 2016, Windows 10, Windows 10 Servers.

Frequently asked questions

What is CVE-2018-8435?: A security feature bypass vulnerability exists when Windows Hyper-V BIOS loader fails to provide a high-entropy source, aka "Windows Hyper-V Security Feature Bypass Vulnerability." This affects Windows Server 2016, Windows 10, Windows 10 Servers.
How severe is CVE-2018-8435?: CVE-2018-8435 has a CVSS 3.x base score of 4.2, rated medium severity. It is exploitable over an adjacent network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2018-8435 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-8435?: CVE-2018-8435 primarily affects Microsoft Windows 10. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-8435?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-8435 published?: CVE-2018-8435 was published on 2018-09-13 and last updated on 2026-06-17.

References

Affected products (8)

cpe:2.3:o:microsoft:windows_10:-:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10:1607:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10:1703:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10:1709:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10:1803:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_server_2016:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2016:1709:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2016:1803:*:*:*:*:*:*:*

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