How severe is CVE-2026-21514?

CVE-2026-21514 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-2026-21514 being actively exploited?

Yes. CVE-2026-21514 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-02-10, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2026-21514?

CVE-2026-21514 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-2026-21514?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2026-21514 have an EU (EUVD) identifier?

Yes. CVE-2026-21514 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7334. It is also flagged as exploited in the EUVD (since 2026-02-10).

When was CVE-2026-21514 published?

CVE-2026-21514 was published on 2026-02-10 and last updated on 2026-06-17.

CVE-2026-21514

CVE-2026-21514 is a high-severity vulnerability in Microsoft 365 Apps with a CVSS 3.x base score of 7.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2026-02-10). The underlying weakness is classified as CWE-807.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 2% (72nd percentile)
Actively exploited: Yes — listed in CISA KEV (added 2026-02-10)
EU (EUVD) id: EUVD-2026-7334
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2026-02-10)
Weakness: CWE-807
Affected product: Microsoft 365 Apps
Published: 2026-02-10
Last modified: 2026-06-17

Description

Reliance on untrusted inputs in a security decision in Microsoft Office Word allows an unauthorized attacker to bypass a security feature locally.

Frequently asked questions

What is CVE-2026-21514?: Reliance on untrusted inputs in a security decision in Microsoft Office Word allows an unauthorized attacker to bypass a security feature locally.
How severe is CVE-2026-21514?: CVE-2026-21514 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-2026-21514 being actively exploited?: Yes. CVE-2026-21514 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-02-10, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2026-21514?: CVE-2026-21514 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-2026-21514?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2026-21514 have an EU (EUVD) identifier?: Yes. CVE-2026-21514 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7334. It is also flagged as exploited in the EUVD (since 2026-02-10).
When was CVE-2026-21514 published?: CVE-2026-21514 was published on 2026-02-10 and last updated on 2026-06-17.

References

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_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:2021:*:*:*:*:macos:*:*
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x64:*
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:-:x86:*
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:macos:*:*

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