How severe is CVE-2026-21517?

CVE-2026-21517 has a CVSS 3.x base score of 4.7, rated medium severity. It is exploitable over local access with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2026-21517 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-21517?

CVE-2026-21517 affects Microsoft Windows App. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-21517?

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

Does CVE-2026-21517 have an EU (EUVD) identifier?

Yes. CVE-2026-21517 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7308.

When was CVE-2026-21517 published?

CVE-2026-21517 was published on 2026-02-10 and last updated on 2026-06-17.

CVE-2026-21517

CVE-2026-21517 is a medium-severity vulnerability in Microsoft Windows App with a CVSS 3.x base score of 4.7. 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-59.

Key facts

Severity: Medium (CVSS 3.x base score 4.7)
EPSS exploit prediction: 0% (28th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-7308
Weakness: CWE-59
Affected product: Microsoft Windows App
Published: 2026-02-10
Last modified: 2026-06-17

Description

Improper link resolution before file access ('link following') in Windows App for Mac allows an authorized attacker to elevate privileges locally.

Frequently asked questions

What is CVE-2026-21517?: Improper link resolution before file access ('link following') in Windows App for Mac allows an authorized attacker to elevate privileges locally.
How severe is CVE-2026-21517?: CVE-2026-21517 has a CVSS 3.x base score of 4.7, rated medium severity. It is exploitable over local access with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2026-21517 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (28th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-21517?: CVE-2026-21517 affects Microsoft Windows App. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-21517?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-21517 have an EU (EUVD) identifier?: Yes. CVE-2026-21517 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7308.
When was CVE-2026-21517 published?: CVE-2026-21517 was published on 2026-02-10 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21517

Affected products (1)

cpe:2.3:a:microsoft:windows_app:*:*:*:*:*:macos:*:*

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