Microsoft Internet Explorer Scripting Engine Memory Corruption Vulnerability

Added to KEV
2021-11-03
Federal due date
2022-05-03
Vendor
Microsoft
Product
Internet Explorer
EPSS
97.2th percentile (score 0.356, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Unknown
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2018-8653

CISA short description

Microsoft Internet Explorer contains a memory corruption vulnerability due to how the Scripting Engine handles objects in memory, leading to remote code execution.

Required action

Apply updates per vendor instructions.

EPSS percentile is the FIRST.org exploit-probability ranking as of the date noted above; it moves daily. CVSS reflects NVD's analysis at time of publication.