How severe is CVE-2026-20830?

CVE-2026-20830 has a CVSS 3.x base score of 7.0, rated high severity. It is exploitable over local access with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-20830 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-20830?

CVE-2026-20830 affects Microsoft Windows Server 2025. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-20830?

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-2026-20830 have an EU (EUVD) identifier?

Yes. CVE-2026-20830 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2207.

When was CVE-2026-20830 published?

CVE-2026-20830 was published on 2026-01-13 and last updated on 2026-06-17.

CVE-2026-20830

CVE-2026-20830 is a high-severity vulnerability in Microsoft Windows Server 2025 with a CVSS 3.x base score of 7.0. 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-362.

Key facts

Severity: High (CVSS 3.x base score 7.0)
EPSS exploit prediction: 0% (21st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-2207
Weakness: CWE-362
Affected product: Microsoft Windows Server 2025
Published: 2026-01-13
Last modified: 2026-06-17

Description

Concurrent execution using shared resource with improper synchronization ('race condition') in Capability Access Management Service (camsvc) allows an authorized attacker to elevate privileges locally.

Frequently asked questions

What is CVE-2026-20830?: Concurrent execution using shared resource with improper synchronization ('race condition') in Capability Access Management Service (camsvc) allows an authorized attacker to elevate privileges locally.
How severe is CVE-2026-20830?: CVE-2026-20830 has a CVSS 3.x base score of 7.0, rated high severity. It is exploitable over local access with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-20830 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-20830?: CVE-2026-20830 affects Microsoft Windows Server 2025. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-20830?: 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-2026-20830 have an EU (EUVD) identifier?: Yes. CVE-2026-20830 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2207.
When was CVE-2026-20830 published?: CVE-2026-20830 was published on 2026-01-13 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20830

Affected products (1)

cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:*

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Other CWE-362 (Race Condition) vulnerabilities

CVE-2022-27626 — Critical (CVSS 10.0): A vulnerability regarding concurrent execution using shared resource with improper synchronization ('Race Condition')…
CVE-2015-8556 — Critical (CVSS 10.0): Local privilege escalation vulnerability in the Gentoo QEMU package before 2.5.0-r1.
CVE-2014-0703 — Critical (CVSS 10.0): Cisco Wireless LAN Controller (WLC) devices 7.4 before 7.4.110.0 distribute Aironet IOS software with a race condition…
CVE-2010-1228 — Critical (CVSS 10.0): Multiple race conditions in the sandbox infrastructure in Google Chrome before 4.1.249.1036 have unspecified impact and…
CVE-2008-6598 — Critical (CVSS 10.0): Multiple race conditions in WANPIPE before 3.3.6 have unknown impact and attack vectors related to "bri restart logic."
CVE-2026-46137 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: mptcp: pm: ADD_ADDR rtx: fix potential…

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