How severe is CVE-2021-34501?

CVE-2021-34501 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-2021-34501 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 53% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34501?

CVE-2021-34501 primarily affects Microsoft 365 Apps. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-34501?

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-2021-34501 published?

CVE-2021-34501 was published on 2021-07-14 and last updated on 2026-06-17.

CVE-2021-34501

CVE-2021-34501 is a high-severity vulnerability in Microsoft 365 Apps with a CVSS 3.x base score of 7.8. Its EPSS exploit-prediction score of 53% places it in the 99th percentile, indicating an elevated likelihood of exploitation.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 6.8
EPSS exploit prediction: 53% (99th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Microsoft 365 Apps
Published: 2021-07-14
Last modified: 2026-06-17

Description

Microsoft Excel Remote Code Execution Vulnerability

Frequently asked questions

What is CVE-2021-34501?: Microsoft Excel Remote Code Execution Vulnerability
How severe is CVE-2021-34501?: CVE-2021-34501 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-2021-34501 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 53% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34501?: CVE-2021-34501 primarily affects Microsoft 365 Apps. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-34501?: 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-2021-34501 published?: CVE-2021-34501 was published on 2021-07-14 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:*:*
cpe:2.3:a:microsoft:excel:2013:sp1:*:*:*:*:*:*
cpe:2.3:a:microsoft:excel:2013:sp1:*:*:rt:*:*:*
cpe:2.3:a:microsoft:excel:2016:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:office:2019:*:*:*:*:-:*:*
cpe:2.3:a:microsoft:office:2019:*:*:*:*:macos:*:*
cpe:2.3:a:microsoft:office_online_server:-:*:*:*:*:*:*:*

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