Cyber Resilience

CVE-2020-1054

HighCISA KEVActive ExploitationEUVD ExploitedPublic PoC

Published: 21 May 2020

Published
21 May 2020
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 0.8146 99.2th percentile
Risk Priority 84 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2020-1054 is a high-severity Out-of-bounds Write (CWE-787) vulnerability in Microsoft Windows 10 1709. Its CVSS base score is 7.8 (High).

Operationally, ranked in the top 0.8% 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 SC-39 (Process Isolation).

Deeper analysis

An elevation of privilege vulnerability exists in Windows when the Windows kernel-mode driver fails to properly handle objects in memory. The issue, tracked as the Win32k Elevation of Privilege Vulnerability and distinct from CVE-2020-1143, carries a CVSS 3.1 score of 7.8 and is associated with CWE-787.

A local attacker with low privileges can exploit the flaw without user interaction to obtain full control over the affected system, resulting in high impact to confidentiality, integrity, and availability.

Microsoft's security advisory and the CISA Known Exploited Vulnerabilities catalog address the issue, directing administrators to apply the corresponding security updates released for supported Windows versions.

The vulnerability appears in public exploit repositories and is listed by CISA as actively used in real-world attacks.

EU & UK References

Vulnerability details

An elevation of privilege vulnerability exists in Windows when the Windows kernel-mode driver fails to properly handle objects in memory, aka 'Win32k Elevation of Privilege Vulnerability'. This CVE ID is unique from CVE-2020-1143.

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 1709
all versions
microsoft
windows 10 1803
all versions
microsoft
windows 10 1809
all versions
microsoft
windows 10 1903
all versions
microsoft
windows 10 1909
all versions
microsoft
windows 7
all versions
microsoft
windows 8.1
all versions
microsoft
windows rt 8.1
all versions
+7 more product configuration(s) — see NVD for full list

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly requires applying the vendor security updates that remediate the Win32k kernel memory-handling flaw.

prevent

Implements memory-protection safeguards that block unauthorized code execution arising from improper object handling in kernel mode.

prevent

Enforces separate execution domains for processes, limiting the ability of a low-privileged local attacker to corrupt kernel objects and escalate privileges.

References