Type Confusion in Microsoft Edge - CVE-2026-66321
Published: July 31, 2026 / Updated: August 2, 2026
Vulnerability identifier: #VU140712
CSH Severity: Medium
CVSS v4 BT: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]
CVE-ID: CVE-2026-66321
CWE-ID: CWE-843
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code.
The vulnerability exists due to access of resource using incompatible type ('type confusion') in Microsoft Edge (Chromium-based) when rendering an attacker-controlled webpage and processing autofill-related user interaction. A remote attacker can host a specially crafted webpage to execute arbitrary code.
User interaction is required: the user must visit an attacker-controlled webpage and perform two tap gestures that cause autofill to activate.
Affected software
Microsoft Edge
How to mitigate CVE-2026-66321
Install security update from vendor's website.
Microsoft Edge - update to 151.0.4129.59