CVE-2018-8174 Microsoft Windows VBScript Engine Out-of-Bounds Write

Exploited in the wild High 7.5 Published 9 May 2018 Updated 13 Aug 2026

Remote code execution via memory corruption in the Windows VBScript engine allows attackers to execute arbitrary code.

Exploited in the wild: Since 15 Feb 2022
Login needed: Not needed
Attackable: Over the internet
Victim action needed: A user has to click or open something
Fix: None listed

What is CVE-2018-8174?

CVE-2018-8174 is a high-severity memory corruption vulnerability in Microsoft Windows 10 1607, published on 9 May 2018. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

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.

Weakness: CWE-787

Which versions are affected by CVE-2018-8174?

It affects 10 products.

Products include Microsoft Windows 10 1607, Microsoft Windows 10 1703, Microsoft Windows 10 1709, Microsoft Windows 10 1803, Microsoft Windows 7, Microsoft Windows 8.1 and 4 more.

How do I fix CVE-2018-8174?

No fix has been published for CVE-2018-8174 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 15 Aug 2022.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2018-8174 being exploited?

Yes. Attackers have exploited CVE-2018-8174 in the wild since at least 15 Feb 2022, including in ransomware campaigns.

Public exploit code: 1 Exploit-DB entry and 9 proofs of concept on GitHub.

All Microsoft Windows 10 1607 vulnerabilities

Sources

Also known as GHSA-5cv8-848m-hmm2.