How severe is CVE-2025-30388?

CVE-2025-30388 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-2025-30388 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-30388?

CVE-2025-30388 primarily affects Microsoft 365 Copilot. In total, 21 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-30388?

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-2025-30388 have an EU (EUVD) identifier?

Yes. CVE-2025-30388 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-14412.

When was CVE-2025-30388 published?

CVE-2025-30388 was published on 2025-05-13 and last updated on 2026-06-17.

CVE-2025-30388

CVE-2025-30388 is a high-severity vulnerability in Microsoft 365 Copilot 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-787.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 3% (88th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-14412
Weakness: CWE-787
Affected product: Microsoft 365 Copilot
Published: 2025-05-13
Last modified: 2026-06-17

Description

Heap-based buffer overflow in Windows Win32K - GRFX allows an unauthorized attacker to execute code locally.

Frequently asked questions

What is CVE-2025-30388?: Heap-based buffer overflow in Windows Win32K - GRFX allows an unauthorized attacker to execute code locally.
How severe is CVE-2025-30388?: CVE-2025-30388 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-2025-30388 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-30388?: CVE-2025-30388 primarily affects Microsoft 365 Copilot. In total, 21 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-30388?: 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-2025-30388 have an EU (EUVD) identifier?: Yes. CVE-2025-30388 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-14412.
When was CVE-2025-30388 published?: CVE-2025-30388 was published on 2025-05-13 and last updated on 2026-06-17.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-30388

Affected products (21)

cpe:2.3:a:microsoft:365_copilot:*:*:*:*:*:android:*:*
cpe:2.3:a:microsoft:office:*:*:*:*:*:universal:*:*
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:macos:*:*
cpe:2.3:a:microsoft:office_long_term_servicing_channel:2024:*:*:*:*:macos:*:*
cpe:2.3:o:microsoft:windows_10_1507:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_10_1607:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_10_1809:*:*:*:*:*:*:x86:*
cpe:2.3:o:microsoft:windows_10_21h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_10_22h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_11_22h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_11_23h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_11_24h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2008:-:sp2:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2008:r2:sp1:*:*:*:*:x64:*
cpe:2.3:o:microsoft:windows_server_2012:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2016:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2019:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2022:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2022_23h2:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2025:*:*:*:*:*:*:*:*

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