How severe is CVE-2021-1732?

CVE-2021-1732 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-1732 being actively exploited?

Yes. CVE-2021-1732 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2021-1732?

CVE-2021-1732 primarily affects Microsoft Windows 10 1803. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-1732?

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-2021-1732 have an EU (EUVD) identifier?

Yes. CVE-2021-1732 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-7196. It is also flagged as exploited in the EUVD (since 2021-11-03).

When was CVE-2021-1732 published?

CVE-2021-1732 was published on 2021-02-25 and last updated on 2026-08-12.

CVE-2021-1732

CVE-2021-1732 is a high-severity vulnerability in Microsoft Windows 10 1803 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 2021-11-03). The underlying weakness is classified as CWE-787.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 4.6
EPSS exploit prediction: 78% (100th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2021-11-03)
EU (EUVD) id: EUVD-2021-7196
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2021-11-03)
Weakness: CWE-787
Affected product: Microsoft Windows 10 1803
Published: 2021-02-25
Last modified: 2026-08-12

Description

Windows Win32k Elevation of Privilege Vulnerability

Frequently asked questions

What is CVE-2021-1732?: Windows Win32k Elevation of Privilege Vulnerability
How severe is CVE-2021-1732?: CVE-2021-1732 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-1732 being actively exploited?: Yes. CVE-2021-1732 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2021-1732?: CVE-2021-1732 primarily affects Microsoft Windows 10 1803. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-1732?: 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-2021-1732 have an EU (EUVD) identifier?: Yes. CVE-2021-1732 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-7196. It is also flagged as exploited in the EUVD (since 2021-11-03).
When was CVE-2021-1732 published?: CVE-2021-1732 was published on 2021-02-25 and last updated on 2026-08-12.

References

Affected products (9)

cpe:2.3:o:microsoft:windows_10_1803:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_10_1809:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_10_1909:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_10_2004:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_10_20h2:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_1909:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2004:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_2019:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows_server_20h2:-:*:*:*:*:*:*:*

More vulnerabilities in Microsoft Windows 10 1803

CVE-2020-1020 — High (CVSS 8.8): A remote code execution vulnerability exists in Microsoft Windows when the Windows Adobe Type Manager Library…
CVE-2019-0903 — High (CVSS 8.8): A remote code execution vulnerability exists in the way that the Windows Graphics Device Interface (GDI) handles…
CVE-2018-8414 — High (CVSS 8.8): A remote code execution vulnerability exists when the Windows Shell does not properly validate file paths, aka "Windows…
CVE-2018-0824 — High (CVSS 8.8): A remote code execution vulnerability exists in "Microsoft COM for Windows" when it fails to properly handle serialized…
CVE-2020-0601 — High (CVSS 8.1): A spoofing vulnerability exists in the way Windows CryptoAPI (Crypt32.dll) validates Elliptic Curve Cryptography (ECC)…
CVE-2022-38396 — High (CVSS 7.8): HP Factory Preinstalled Images on certain systems that shipped with Windows 10 versions 20H2 and earlier OS versions…

All CVEs affecting Microsoft Windows 10 1803 →

Other CWE-787 (Out-of-bounds Write) vulnerabilities

CVE-2026-42369 — Critical (CVSS 10.0): GV-VMS V20 is a Video Monitoring Software used to gather the feeds of many surveillance cameras and manage other…
CVE-2026-4746 — Critical (CVSS 10.0): Out-of-bounds Write vulnerability in timeplus-io proton (base/poco/Foundation/src‎ modules). This vulnerability is…
CVE-2025-43300 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 15.8.5 and iPadOS…
CVE-2025-24201 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved checks to prevent unauthorized actions. This issue is fixed in…
CVE-2024-42479 — Critical (CVSS 10.0): llama.cpp provides LLM inference in C/C++. The unsafe `data` pointer member in the `rpc_tensor` structure can cause…
CVE-2024-39791 — Critical (CVSS 10.0): Stack-based buffer overflow vulnerabilities affecting Vonets industrial wifi bridge relays and wifi bridge…

Browse all CWE-787 (Out-of-bounds Write) vulnerabilities →