What is CVE-2026-97381?

CVE-2026-97381 is a critical-severity vulnerability in Legacyupdate, classified under Origin Validation Error. CVSS score: 9.9/10. Published 2026-10-13.

How severe is CVE-2026-97381?

Critical severity. CVSS v3 base score is 9.9 out of 10.

Vulnerability in Legacyupdate

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 restart the computer when a reboot is pending. This issue was fixed in Legacy Update 1.13.2.

Published 2026-10-13.

CVSS v3 metric

CVSS v3 base score 9.9 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Legacyupdate — versions >= 1.12.0, < 1.13.2

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-97381?: CVE-2026-97381 is a critical-severity vulnerability in Legacyupdate, classified under Origin Validation Error. CVSS score: 9.9/10. Published 2026-10-13.
How severe is CVE-2026-97381?: Critical severity. CVSS v3 base score is 9.9 out of 10.