CVE-2018-8174 — Windows 7
HIGHCVE-2018-8174 is a high-severity (CVSS 7.5) Out-of-bounds Write vulnerability in microsoft windows 7. It is in CISA's Known Exploited Vulnerabilities catalog (added 2022-02-15) and has been used in ransomware campaigns — treat it as actively exploited and patch now. No vendor fix is recorded yet; mitigation options are listed below.
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…
Exploitation Status
Actively exploited in the wild
- Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2022-02-15 — including use in ransomware campaigns. Federal agencies were required to remediate by 2022-08-15.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2018-8174.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2018-8174 by exploitation likelihood (EPSS) against impact (CVSS). In the shaded patch-first corner (EPSS 50%+, CVSS 7.0+).
Where this sits among everything scored
Of 394,803 CVEs with a current EPSS score, this one falls in the 50–90% band (highlighted). Counts from FIRST.org, log-scaled.
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.
Affected Products
windows 7microsoftwindows 8.1microsoftwindows 10 1607microsoftwindows 10 1703microsoftwindows 10 1709microsoftwindows 10 1803microsoftResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Microsoft Internet Explorer 11 (Windows 7 x86/x64) - vbscript Code Execution
by smgorelik · May 21, 2018
Detection & mitigation playbook
Vendor / applianceDetect
Inventory every microsoft windows 7 deployment and check each version against the affected-products list above.
Remediation status
No patch has shipped for CVE-2018-8174 yet — track the microsoft windows 7 advisory for a fixed release and apply the workarounds below in the meantime.
Mitigate without a patch
Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.
Frequently Asked Questions
Is CVE-2018-8174 being exploited in your environment?
Detect and block the exploit chain at execution, on systems you cannot patch yet.