Microsoft Windows Common Log File System (CLFS) Driver Privilege Escalation Vulnerability

Windows Common Log File System Driver Elevation of Privilege Vulnerability

CheckOps priority index

6.4/10 Patch within 7 days

Severity7.8

Probability2.8

Exploitation4/5

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

EPSS · today 28.5% +0.2 pts in 7 days

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

Exploited for 1,511 days 14 Sept 2022

CISA due date 05 Oct 2022 for US federal agencies

Exploitation probability EPSS · FIRST

EPSS probability (%)Percentile among all CVEs

Exploitation signals 4 / 5

KEV catalog (CISA)14 Sept 2022
Exploited in EUVD (ENISA)14 Sept 2022
Used by ransomwareyes
EPSS above 10 %28.5%
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

Affected products

Windows Server 2016 (Server Core installation)Windows Server 2012 R2Windows Server 2012 (Server Core installation)Windows Server 2008 Service Pack 2Windows 10 Version 1809Windows Server 2008 Service Pack 2Windows Server 2019Windows Server 2016Windows 10 Version 1507Windows 8.1Windows 11 version 21H2Windows Server 2012 R2 (Server Core installation)Windows Server 2019 (Server Core installation)Windows 10 Version 20H2Windows Server 2012Windows Server 2022Windows 7Windows 7 Service Pack 1Windows Server 2008 R2 Service Pack 1 (Server Core installation)Windows 10 Version 21H1Windows Server 2008 Service Pack 2 (Server Core installation)Windows 10 Version 21H2Windows 10 Version 1607Windows Server 2008 R2 Service Pack 1Windows

Affected versions

10.0.14393.0 <10.0.14393.5356
6.3.9600.0 <6.3.9600.20571
6.2.9200.0 <6.2.9200.23865
6.0.6003.0 <6.0.6003.21666
10.0.0 <10.0.17763.3406
10.0.17763.0 <10.0.17763.3406
10.0.10240.0 <10.0.10240.19444
6.3.0 <6.3.9600.20571
10.0.0 <10.0.22000.978
10.0.0 <10.0.19042.2006
10.0.20348.0 <10.0.20348.1006
6.1.0 <6.1.7601.26115

Weaknesses (CWE)

CWE-20 CWE-787

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

13 Sept 2022
Published
14 Sept 2022
Exploitation reported (ENISA)
14 Sept 2022
Added to the KEV catalog
05 Oct 2022
CISA remediation due date
29 Oct 2026
EPSS peak: 28.5%

References

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