How severe is CVE-2021-38654?

CVE-2021-38654 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-2021-38654 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-38654?

CVE-2021-38654 primarily affects Microsoft 365 Apps. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-38654?

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.

When was CVE-2021-38654 published?

CVE-2021-38654 was published on 2021-09-15 and last updated on 2026-06-17.

CVE-2021-38654

CVE-2021-38654 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-129.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 6.8
EPSS exploit prediction: 5% (91st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-129
Affected product: Microsoft 365 Apps
Published: 2021-09-15
Last modified: 2026-06-17

Description

Microsoft Office Visio Remote Code Execution Vulnerability

Frequently asked questions

What is CVE-2021-38654?: Microsoft Office Visio Remote Code Execution Vulnerability
How severe is CVE-2021-38654?: CVE-2021-38654 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-2021-38654 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-38654?: CVE-2021-38654 primarily affects Microsoft 365 Apps. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-38654?: 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.
When was CVE-2021-38654 published?: CVE-2021-38654 was published on 2021-09-15 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:*:*
cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:*:*

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