CVE-2026-48571 Microsoft CVE debrief

Who should care

Administrators and users of Windows App Installer should be aware of this vulnerability, as it allows an authorized attacker to elevate privileges locally. This could lead to a significant impact on the system, including unauthorized access to sensitive data and disruption of system operations. Administrators should verify the Windows App Installer version and ensure it is up-to-date.

Technical summary

CVE-2026-48571 is a use-after-free vulnerability in Windows App Installer. The vulnerability has a CVSS score of 7 and is classified as HIGH severity. The CVSS vector is CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H. This vulnerability allows an authorized attacker to elevate privileges locally, which could lead to a significant impact on the system. The vulnerability is caused by a use-after-free error in the Windows App Installer. Administrators should verify the Windows App Installer version and ensure it is up-to-date.

Defensive priority

High priority should be given to patching this vulnerability, as it allows for local privilege escalation.

Recommended defensive actions

• Apply the patch provided by the vendor
• Verify that the Windows App Installer is up-to-date
• Monitor for any suspicious activity related to the vulnerability
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record was published on 2026-07-14T17:16:50.023Z and has not been modified since then. The NVD entry is currently Undergoing Analysis. Administrators should verify the Windows App Installer version and ensure it is up-to-date. The vulnerability allows an authorized attacker to elevate privileges locally, which could lead to a significant impact on the system. There is no evidence of exploitation in the wild, but defenders should monitor for suspicious activity related to the vulnerability.

Official resources