How severe is CVE-2026-45654?

CVE-2026-45654 has a CVSS 3.x base score of 7.9, rated high 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 none.

Is CVE-2026-45654 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-45654?

CVE-2026-45654 primarily affects Microsoft Windows 11 24h2. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-45654?

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.

Does CVE-2026-45654 have an EU (EUVD) identifier?

Yes. CVE-2026-45654 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35570.

When was CVE-2026-45654 published?

CVE-2026-45654 was published on 2026-06-09 and last updated on 2026-06-17.

CVE-2026-45654

CVE-2026-45654 is a high-severity vulnerability in Microsoft Windows 11 24h2 with a CVSS 3.x base score of 7.9. 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-284.

Key facts

Severity: High (CVSS 3.x base score 7.9)
EPSS exploit prediction: 0% (23rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-35570
Weakness: CWE-284
Affected product: Microsoft Windows 11 24h2
Published: 2026-06-09
Last modified: 2026-06-17

Description

Protection mechanism failure in Windows Secure Boot allows an authorized attacker to bypass a security feature locally.

Frequently asked questions

What is CVE-2026-45654?: Protection mechanism failure in Windows Secure Boot allows an authorized attacker to bypass a security feature locally.
How severe is CVE-2026-45654?: CVE-2026-45654 has a CVSS 3.x base score of 7.9, rated high 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 none.
Is CVE-2026-45654 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-45654?: CVE-2026-45654 primarily affects Microsoft Windows 11 24h2. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-45654?: 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.
Does CVE-2026-45654 have an EU (EUVD) identifier?: Yes. CVE-2026-45654 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-35570.
When was CVE-2026-45654 published?: CVE-2026-45654 was published on 2026-06-09 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45654

Affected products (7)

cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:arm64:*
cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:arm64:*
cpe:2.3:o:microsoft:windows_11_25h2:*:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:*
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:x64:*

More vulnerabilities in Microsoft Windows 11 24h2

CVE-2025-49708 — Critical (CVSS 9.9): Use after free in Microsoft Graphics Component allows an authorized attacker to elevate privileges over a network.
CVE-2026-47291 — Critical (CVSS 9.8): Integer overflow or wraparound in Windows HTTP.sys allows an unauthorized attacker to execute code over a network.
CVE-2026-45657 — Critical (CVSS 9.8): Use after free in Windows Kernel allows an unauthorized attacker to execute code over a network.
CVE-2026-44815 — Critical (CVSS 9.8): Stack-based buffer overflow in Windows DHCP Client allows an unauthorized attacker to execute code over a network.
CVE-2026-41096 — Critical (CVSS 9.8): Heap-based buffer overflow in Microsoft Windows DNS allows an unauthorized attacker to execute code over a network.
CVE-2026-33824 — Critical (CVSS 9.8): Double free in Windows IKE Extension allows an unauthorized attacker to execute code over a network.

All CVEs affecting Microsoft Windows 11 24h2 →

Other CWE-284 (Improper Access Control) vulnerabilities

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CVE-2026-35307 — Critical (CVSS 10.0): Vulnerability in the Oracle Coherence product of Oracle Fusion Middleware (component: Core). Supported versions that…
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CVE-2026-46840 — Critical (CVSS 10.0): Vulnerability in Oracle REST Data Services (component: Backend-as-a-Service). Supported versions that are affected are…

Browse all CWE-284 (Improper Access Control) vulnerabilities →