Cyber Resilience

CVE-2019-0803

HighCISA KEVActive ExploitationEUVD ExploitedPublic PoC

Published: 09 April 2019

Published
09 April 2019
Modified
29 October 2025
KEV Added
03 November 2021
Patch
CVSS Score v3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.8884 99.5th percentile
Risk Priority 89 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2019-0803 is a high-severity an unspecified weakness vulnerability in Microsoft Windows 10 1709. Its CVSS base score is 7.8 (High).

Operationally, ranked in the top 0.5% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 SI-2 (Flaw Remediation) and AC-6 (Least Privilege).

Deeper analysis

CVE-2019-0803 is an elevation of privilege vulnerability in the Windows Win32k component that arises when the driver fails to properly handle objects in memory. The flaw affects supported Windows releases and carries a CVSS 3.1 base score of 7.8, reflecting local attack vector, low complexity, and no user interaction requirements.

A local attacker with existing low-privileged access can exploit the issue to corrupt memory objects, thereby obtaining full administrative privileges on the affected system and gaining the ability to read, write, or delete arbitrary data.

Microsoft’s security advisory and the CISA Known Exploited Vulnerabilities catalog both reference the flaw, indicating that official patches are available through standard Windows Update channels and that organizations should apply them promptly to prevent exploitation.

The vulnerability appears in public exploit repositories and is tracked by CISA as actively used in the wild, underscoring the need for rapid remediation on any remaining unpatched endpoints.

EU & UK References

Vulnerability details

An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in memory, aka 'Win32k Elevation of Privilege Vulnerability'. This CVE ID is unique from CVE-2019-0685, CVE-2019-0859.

CWE(s)
KEV Date Added
03 November 2021

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

microsoft
windows 10 1507
all versions
microsoft
windows 10 1607
all versions
microsoft
windows 10 1703
all versions
microsoft
windows 10 1709
all versions
microsoft
windows 10 1803
all versions
microsoft
windows 10 1809
all versions
microsoft
windows 7
all versions
microsoft
windows 8.1
all versions
microsoft
windows rt 8.1
all versions
microsoft
windows server 1709
all versions
+5 more product configuration(s) — see NVD for full list

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly requires timely application of the vendor patch that eliminates the Win32k memory-object flaw before local exploitation can succeed.

prevent

Mandates memory-protection safeguards that would block the unauthorized object corruption Win32k fails to prevent.

prevent

Enforces least-privilege boundaries so that even a successful local exploit yields only the minimal rights the process was originally granted.

References