CVE-2026-20830
High CVSS 7Published 2026-01-13 ยท last changed 2026-06-17
The fix
Microsoft fixes this in updateKB5073379. 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 Server 2025 | 10.0.26100.32230 | KB5073379 | 2026-09-20 |
| Windows Server 2025 (Server Core installation) | 10.0.26100.32230 | KB5073379 | 2026-09-20 |
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
Concurrent execution using shared resource with improper synchronization ('race condition') in Capability Access Management Service (camsvc) allows an authorized attacker to elevate privileges locally.
Sources
CVSS vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H