Background exploitation KEV catalog Ransomware No authentication

CVE-2018-8174

Microsoft Windows VBScript Engine Out-of-Bounds Write Vulnerability

CheckOps priority index

8.6/10 Patch within 24 h

Severity7.5

Probability8.8

Exploitation5/5

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

EPSS · today 88.2% higher than 99.8% of CVEs

CVSS 3.1 7.5 AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:

Exploited for 1,722 days 15 Feb 2022

CISA due date 15 Aug 2022 for US federal agencies

Exploitation probability EPSS · FIRST

EPSS probability (%)Percentile among all CVEs

Exploitation signals 5 / 5

KEV catalog (CISA)15 Feb 2022
Exploited in EUVD (ENISA)15 Feb 2022
Used by ransomwareyes
EPSS above 10 %88.2%
No account, over the networkyes

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

A remote code execution vulnerability exists in the way that the VBScript engine handles objects in memory, aka "Windows VBScript Engine Remote Code Execution Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Windows Server 2012, Windows 8.1, Windows Server 2016, Windows Server 2008 R2, Windows 10, Windows 10 Servers.

Affected products

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

Affected versions

x64-based Systems Service Pack 1
(Server Core installation)
version 1709 (Server Core Installation)
x64-based systems
x64-based Systems Service Pack 2 (Server Core installation)
x64-based Systems Service Pack 1 (Server Core installation)
Version 1803 for 32-bit Systems
x64-based Systems Service Pack 2
Version 1803 for x64-based Systems
32-bit Systems Service Pack 2
version 1803 (Server Core Installation)
x64-based Systems

Weaknesses (CWE)

CWE-787

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

09 May 2018
Published
15 Feb 2022
Exploitation reported (ENISA)
15 Feb 2022
Added to the KEV catalog
15 Aug 2022
CISA remediation due date
26 Sept 2026
EPSS peak: 88.3%

References

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