How severe is CVE-2025-21354?

CVE-2025-21354 has a CVSS 3.x base score of 8.4, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-21354 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-21354?

CVE-2025-21354 primarily affects Microsoft 365 Apps. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-21354?

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-2025-21354 have an EU (EUVD) identifier?

Yes. CVE-2025-21354 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-2418.

When was CVE-2025-21354 published?

CVE-2025-21354 was published on 2025-01-14 and last updated on 2026-06-17.

CVE-2025-21354

CVE-2025-21354 is a high-severity vulnerability in Microsoft 365 Apps with a CVSS 3.x base score of 8.4. 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-822.

Key facts

Severity: High (CVSS 3.x base score 8.4)
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-2418
Weakness: CWE-822
Affected product: Microsoft 365 Apps
Published: 2025-01-14
Last modified: 2026-06-17

Description

Microsoft Excel Remote Code Execution Vulnerability

Frequently asked questions

What is CVE-2025-21354?: Microsoft Excel Remote Code Execution Vulnerability
How severe is CVE-2025-21354?: CVE-2025-21354 has a CVSS 3.x base score of 8.4, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-21354 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-21354?: CVE-2025-21354 primarily affects Microsoft 365 Apps. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-21354?: 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-2025-21354 have an EU (EUVD) identifier?: Yes. CVE-2025-21354 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-2418.
When was CVE-2025-21354 published?: CVE-2025-21354 was published on 2025-01-14 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21354

Affected products (11)

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: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:*:*
cpe:2.3:a:microsoft:office_online_server:*:*:*:*:*:*:*:*

More vulnerabilities in Microsoft 365 Apps

CVE-2024-21413 — Critical (CVSS 9.8): Microsoft Outlook Remote Code Execution Vulnerability
CVE-2023-23397 — Critical (CVSS 9.8): Microsoft Outlook Elevation of Privilege Vulnerability
CVE-2020-0901 — Critical (CVSS 9.8): A remote code execution vulnerability exists in Microsoft Excel software when the software fails to properly handle…
CVE-2023-33150 — Critical (CVSS 9.6): Microsoft Office Security Feature Bypass Vulnerability
CVE-2026-40420 — High (CVSS 8.8): Use after free in Microsoft Office allows an authorized attacker to elevate privileges locally.
CVE-2026-35436 — High (CVSS 8.8): Use after free in Microsoft Office allows an authorized attacker to elevate privileges locally.

All CVEs affecting Microsoft 365 Apps →

Other CWE-822 vulnerabilities

CVE-2025-50165 — Critical (CVSS 9.8): Untrusted pointer dereference in Microsoft Graphics Component allows an unauthorized attacker to execute code over a…
CVE-2023-1437 — Critical (CVSS 9.8): All versions prior to 9.1.4 of Advantech WebAccess/SCADA are vulnerable to use of untrusted pointers. The RPC arguments…
CVE-2026-48137 — Critical (CVSS 9.1): There is an untrusted pointer dereference vulnerability in the NI grpc-device sideband streaming API that may allow an…
CVE-2025-4993 — Critical (CVSS 9.1): Untrusted Pointer Dereference vulnerability in RTI Connext Professional (Core Libraries) allows Pointer…
CVE-2025-1255 — Critical (CVSS 9.1): Untrusted Pointer Dereference vulnerability in RTI Connext Professional (Core Libraries) allows Pointer…
CVE-2024-36461 — Critical (CVSS 9.1): Within Zabbix, users have the ability to directly modify memory pointers in the JavaScript engine.

Browse all CWE-822 vulnerabilities →