Background exploitation KEV catalog Ransomware

CVE-2018-8453

Microsoft Win32k Privilege Escalation Vulnerability

CheckOps priority index

7.6/10 Patch within 7 days

Severity7.8

Probability7.0

Exploitation4/5

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

EPSS · today 70.0% higher than 99.4% of CVEs

CVSS 3.1 7.8 AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:

Exploited for 1,747 days 21 Jan 2022

CISA due date 21 Jul 2022 for US federal agencies

Exploitation probability EPSS · FIRST

EPSS probability (%)Percentile among all CVEs

Exploitation signals 4 / 5

KEV catalog (CISA)21 Jan 2022
Exploited in EUVD (ENISA)21 Jan 2022
Used by ransomwareyes
EPSS above 10 %70.0%
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 Win32k component fails to properly handle objects in memory, aka "Win32k Elevation of Privilege Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Windows Server 2019, Windows Server 2012, Windows 8.1, Windows Server 2016, Windows Server 2008 R2, Windows 10, Windows 10 Servers.

Affected products

Windows Server 2008Windows 10Windows Server 2008 R2Windows 7Windows Server 2012Windows Server 2016Windows 8.1Windows Server 2012 R2Windows Server 2019Windows 10 ServersWindows RT 8.1Win32k

Affected versions

32-bit Systems Service Pack 2
32-bit Systems
Itanium-Based Systems Service Pack 1
x64-based Systems Service Pack 1
32-bit Systems Service Pack 1
(Server Core installation)
x64-based Systems Service Pack 1 (Server Core installation)
x64-based systems
Version 1809 for x64-based Systems
Version 1703 for 32-bit Systems
version 1803 (Server Core Installation)
x64-based Systems

Weaknesses (CWE)

CWE-404

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

10 Oct 2018
Published
21 Jan 2022
Exploitation reported (ENISA)
21 Jan 2022
Added to the KEV catalog
21 Jul 2022
CISA remediation due date
26 Sept 2026
EPSS peak: 70.0%

References

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