CVE-2026-20858CWE-362CWE-416

CVE-2026-20858

High · published January 13, 2026

CVSS v3.1
7.8
EPSS
0%
Percentile
20.8
In the wild
Unconfirmed
What it is

⚡ An authorized attacker can exploit this use-after-free flaw to elevate privileges in Windows Management Services, as if an employee suddenly discovers a secret room in the office with no one watching! 🔥 Think of the use-after-free vulnerability like a hotel room key that hasn't been deactivated after a guest checks out. If the next guest can still access the room, they can rummage around and do whatever they please, which is exactly what could happen here. If exploited, an attacker could gain elevated privileges on the local system, allowing them to bypass restrictions and control sensitive operations. This could lead to unauthorized data access, system modifications, or even full control—definitely a recipe for chaos!

Put simply

Think of the use-after-free vulnerability like a hotel room key that hasn't been deactivated after a guest checks out. If the next guest can still access the room, they can rummage around and do whatever they please, which is exactly what could happen here. This vulnerability occurs when the Windows Management Services does not properly manage memory after freeing up resources. An attacker with valid access can manipulate this oversight to escalate their privileges locally.

What to do

If exploited, an attacker could gain elevated privileges on the local system, allowing them to bypass restrictions and control sensitive operations. This could lead to unauthorized data access, system modifications, or even full control—definitely a recipe for chaos! To mitigate this vulnerability, ensure that your system is updated with the latest security patches from Microsoft. Regularly audit user privileges and limit access to those who truly need it. It's also wise to implement network segmentation to reduce potential attack surfaces. You've got this! By staying proactive and following these steps, you can secure your systems and enjoy some peace of mind! 🛡️

The record
Technical detail
CVSS v3.1
7.8 · HIGH
Vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00293 · 20.8th percentile
Weaknesses
CWE-362 · Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition'); CWE-416 · Use After Free
Published
2026-01-13T23:16Z
Affected products (11)
ProductVersionsFixed in
microsoft/windows_10_1809< 10.0.17763.827610.0.17763.8276
microsoft/windows_10_1809< 10.0.17763.827610.0.17763.8276
microsoft/windows_10_21h2< 10.0.19044.680910.0.19044.6809
microsoft/windows_10_22h2< 10.0.19045.680910.0.19045.6809
microsoft/windows_11_23h2< 10.0.22631.649110.0.22631.6491
microsoft/windows_11_24h2< 10.0.26100.762310.0.26100.7623
microsoft/windows_11_25h2< 10.0.26200.762310.0.26200.7623
microsoft/windows_server_2019< 10.0.17763.827610.0.17763.8276
microsoft/windows_server_2022< 10.0.20348.464810.0.20348.4648
microsoft/windows_server_2022_23h2< 10.0.25398.209210.0.25398.2092
microsoft/windows_server_2025< 10.0.26100.3223010.0.26100.32230
References (1)
EPSS history
Timeline
  • 13 JAN 17:56Z
    Windows Management Services Elevation of Privilege Vulnerability
    cvelistv5