Background exploitation KEV catalog

CVE-2020-1054

Microsoft Win32k Privilege Escalation Vulnerability

CheckOps priority index

6.2/10 Patch within 7 days

Severity7.0

Probability5.4

Exploitation3/5

Severity = CVSS. Probability = EPSS (FIRST). Exploitation = public signals: KEV, EUVD, ransomware, EPSS above 10 %, no account required.

EPSS · today 53.9% higher than 99.0% of CVEs

CVSS 3.1 7.0 AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:

Exploited for 1,827 days 03 Nov 2021

CISA due date 03 May 2022 for US federal agencies

Exploitation probability EPSS · FIRST

EPSS probability (%)Percentile among all CVEs

Exploitation signals 3 / 5

KEV catalog (CISA)03 Nov 2021
Exploited in EUVD (ENISA)03 Nov 2021
Used by ransomwareno
EPSS above 10 %53.9%
No account, over the networkno

What to do

Fix

Apply the vendor’s fix as soon as it is available.

CISA guidance: Apply updates per vendor instructions.

Meanwhile

Take the service off the internet or restrict access to it, watch the logs and look for signs of compromise.

Manufacturers (CRA)

Exploited vulnerability in your product: early warning to ENISA within 24 h, then notification within 72 h (Article 14 of the Cyber Resilience Act). The CRA explained

Description ENISA EUVD

An elevation of privilege vulnerability exists in Windows when the Windows kernel-mode driver fails to properly handle objects in memory. An attacker who successfully exploited this vulnerability could run arbitrary code in kernel mode. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. To exploit this vulnerability, an attacker would first have to log on to the system. An attacker could then run a specially crafted application that could exploit the vulnerability and take control of an affected system. The update addresses this vulnerability by correcting how the Windows kernel-mode driver handles objects in memory.

Affected products

Windows 7Windows Server 2008 Service Pack 2Windows Server 2012 R2Windows Server 2012 R2 (Server Core installation)Windows 10 Version 1803Windows Server 2019Windows 10 Version 1709Windows Server, version 1803 (Server Core Installation)Windows 10 Version 1903 for x64-based SystemsWindows 10 Version 1607Windows 10 Version 1809Windows Server 2016 (Server Core installation)Windows Server, version 1903 (Server Core installation)Windows 10 Version 1903 for 32-bit SystemsWindows 8.1Windows 10 Version 1709 for 32-bit SystemsWindows 7 Service Pack 1Windows Server 2008 Service Pack 2 (Server Core installation)Windows Server 2012 (Server Core installation)Windows Server 2016Windows 10 Version 1507Windows 10 Version 1903 for ARM64-based SystemsWindows Server 2008 R2 Service Pack 1 (Server Core installation)Windows Server, version 1909 (Server Core installation)Windows Server 2019 (Server Core installation)Windows Server 2008 R2 Service Pack 1Windows Server 2012Windows 10 Version 1909Win32k

Affected versions

6.1.0 <publication
6.0.6003.0 <publication
6.3.9600.0 <publication
10.0.0 <publication
10.0.17763.0 <publication
10.0.14393.0 <publication
6.3.0 <publication
6.2.9200.0 <publication
10.0.10240.0 <publication
6.1.7601.0 <publication

Weaknesses (CWE)

CWE-787

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

21 May 2020
Published
03 Nov 2021
Exploitation reported (ENISA)
03 Nov 2021
Added to the KEV catalog
03 May 2022
CISA remediation due date
26 Sept 2026
EPSS peak: 54.2%

References

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