CVE-2026-121678
Medium CVSS 5.3Published 2026-11-10 ยท last changed 2026-11-10
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 | 2.0.1489.0 | configuration change | 2026-11-10 |
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
Out-of-bounds read in Remote Desktop Client allows an unauthorized attacker to disclose information over a network.
Sources
CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N