Microsoft Win32k Privilege Escalation Vulnerability

CheckOps priority index

7.5/10 Patch within 7 days

Severity7.8

Probability8.7

Exploitation3/5

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

EPSS · today 86.6% higher than 99.7% of CVEs

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

Exploited for 1,644 days 04 May 2022

CISA due date 25 May 2022 for US federal agencies

Exploitation probability EPSS · FIRST

EPSS probability (%)Percentile among all CVEs

Exploitation signals 3 / 5

KEV catalog (CISA)04 May 2022
Exploited in EUVD (ENISA)04 May 2022
Used by ransomwareno
EPSS above 10 %86.6%
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

win32k.sys in the kernel-mode drivers in Microsoft Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8, Windows 8.1, Windows Server 2012 Gold and R2, and Windows RT Gold and 8.1 allows local users to gain privileges via a crafted application, as exploited in the wild in October 2014, aka "Win32k.sys Elevation of Privilege Vulnerability."

Affected products

Win32k

Weaknesses (CWE)

CWE-264

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

15 Oct 2014
Published
04 May 2022
Exploitation reported (ENISA)
04 May 2022
Added to the KEV catalog
25 May 2022
CISA remediation due date
26 Sept 2026
EPSS peak: 86.9%

References

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