How severe is CVE-2025-21356?

CVE-2025-21356 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-21356 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-21356?

CVE-2025-21356 primarily affects Microsoft 365 Apps. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-21356?

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-2025-21356 have an EU (EUVD) identifier?

Yes. CVE-2025-21356 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-2419.

When was CVE-2025-21356 published?

CVE-2025-21356 was published on 2025-01-14 and last updated on 2026-06-17.

CVE-2025-21356

CVE-2025-21356 is a high-severity vulnerability in Microsoft 365 Apps with a CVSS 3.x base score of 7.8. 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-122.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 1% (49th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-2419
Weakness: CWE-122
Affected product: Microsoft 365 Apps
Published: 2025-01-14
Last modified: 2026-06-17

Description

Microsoft Office Visio Remote Code Execution Vulnerability

Frequently asked questions

What is CVE-2025-21356?: Microsoft Office Visio Remote Code Execution Vulnerability
How severe is CVE-2025-21356?: CVE-2025-21356 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-21356 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-21356?: CVE-2025-21356 primarily affects Microsoft 365 Apps. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-21356?: 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-2025-21356 have an EU (EUVD) identifier?: Yes. CVE-2025-21356 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-2419.
When was CVE-2025-21356 published?: CVE-2025-21356 was published on 2025-01-14 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21356

Affected products (8)

cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:*
cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:*
cpe:2.3:a:microsoft:office:2019:*:*:*:*:-:x64:*
cpe:2.3:a:microsoft:office:2019:*:*:*:*:-:x86:*
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:*:x64:*
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:*:x86:*
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:*:x64:*
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:*:x86:*

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