CVE-2026-23656
Medium CVSS 5.9Published 2026-03-10 ยท last changed 2026-06-17
The fix
Microsoft publishes remediation for this across 1 product branch. The fixed build differs per Windows version, so the row that matters is the one matching the machine you are looking at.
| Windows version | Fixed in build | Update | Released |
|---|---|---|---|
| Windows App Client for Windows Desktop | 2.0.964 | configuration change | 2026-09-17 |
Having the KB is not the same as knowing whether a machine has it. Windows updates supersede each other, so the update you installed often covers a fix that shipped in an earlier one. Paste your build into the patch checker and it walks that chain for you.
What it is
Insufficient verification of data authenticity in Windows App Installer allows an unauthorized attacker to perform spoofing over a network.
Sources
CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N