Microsoft Win32k Privilege Escalation Vulnerability

CheckOps priority index

5.3/10 Patch within 7 days

Severity7.8

Probability1.4

Exploitation3/5

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

EPSS · today 13.7% higher than 96.5% of CVEs

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

Exploited for 1,230 days 22 Jun 2023

CISA due date 13 Jul 2023 for US federal agencies

Exploitation probability EPSS · FIRST

EPSS probability (%)Percentile among all CVEs

Exploitation signals 3 / 5

KEV catalog (CISA)22 Jun 2023
Exploited in EUVD (ENISA)22 Jun 2023
Used by ransomwareno
EPSS above 10 %13.7%
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

The kernel-mode driver in Microsoft Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8.1, Windows Server 2012 Gold and R2, Windows RT 8.1, and Windows 10 Gold and 1511 allows local users to gain privileges via a crafted application, aka "Win32k Elevation of Privilege Vulnerability," a different vulnerability than CVE-2016-0143 and CVE-2016-0167.

Affected products

Win32k

Weaknesses (CWE)

CWE-264

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

12 Apr 2016
Published
22 Jun 2023
Exploitation reported (ENISA)
22 Jun 2023
Added to the KEV catalog
13 Jul 2023
CISA remediation due date
26 Sept 2026
EPSS peak: 13.7%

References

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