What’s Vulnerable › Vulnerabilities

CVE-2020-1064: MSHTML Engine Remote Code Execution Vulnerability

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 3.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2020-05-21 · updated 2026-08-19

Description

A remote code execution vulnerability exists in the way that the MSHTML engine improperly validates input. An attacker could execute arbitrary code in the context of the current user. If the current user is logged on with administrative user rights, an attacker who successfully exploited the vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. In a HTML editing attack scenario, an attacker could trick a user into editing a specially crafted file that is designed to exploit the vulnerability. The security update addresses the vulnerability by modifying how MSHTML engine validates input.

Affected products

• Microsoft Internet Explorer 11: 9, 11
• Microsoft Internet Explorer 11: from 1.0.0 before publication — fixed in publication
• Microsoft Internet Explorer 9: from 1.0.0 before publication — fixed in publication

How to fix

Upgrade to a fixed version: Microsoft Internet Explorer 11 publication; Microsoft Internet Explorer 9 publication. Check the vendor advisory for mitigations.

References

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2020-1064
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1064

Get alerted when CVE-2020-1064 or the next vulnerability affects your stack