- Critical 9.9
CVE-2026-97381
Legacy Update is a tool for activating and installing updates on legacy Windows PCs. Legacy Update 1.12.0 through 1.13.1 contains an origin validation error in the IsPermitted method of its ActiveX control. After successfully reading the hosting document's hostname, a hostname that is not on the permitted list falls through without setting E_ACCESSDENIED, causing IsPermitted to return S_OK. An attacker who induces a user to visit a malicious webpage in Internet Explorer can invoke the control to enumerate update and system information, install updates without consent, display dialogs, or rest…
Scores
The facts
- Published
- 13 October 2026
- Last changed
- 17 October 2026
- NVD status
- Deferred
- Severity
- Critical, CVSS 9.9 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H - Weakness
- Known exploited
- Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
- EPSS
- 0.2% chance of exploitation activity in the next 30 days (percentile 11).
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