CVE-2026-20810CWE-590

Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability

High · published January 13, 2026

CVSS v3.1
7.8
EPSS
0%
Percentile
41.1
In the wild
Unconfirmed
What it is

⚡ A local attacker could exploit a sneaky memory management flaw in the Windows Ancillary Function Driver for WinSock, which means privilege elevation is just around the corner! 🔥 Think of it like finding an escape route in a building that shouldn't be accessed—once you know the way, you can access all the offices you want. This vulnerability allows an authorized user to step through the back door into higher privileges they shouldn’t have access to. If exploited, this vulnerability could lead a local attacker to gain unauthorized control over system functions, allowing them to install programs, view sensitive data, or even change settings that could jeopardize the entire system's integrity. Without proper management, the consequences could be absolutely devastating!

Put simply

Think of it like finding an escape route in a building that shouldn't be accessed—once you know the way, you can access all the offices you want. This vulnerability allows an authorized user to step through the back door into higher privileges they shouldn’t have access to. This vulnerability arises from memory being incorrectly freed in a way that isn't associated with the heap in the Windows Ancillary Function Driver for WinSock. This oversight creates an opportunity for authorized users to elevate their privileges unexpectedly.

What to do

If exploited, this vulnerability could lead a local attacker to gain unauthorized control over system functions, allowing them to install programs, view sensitive data, or even change settings that could jeopardize the entire system's integrity. Without proper management, the consequences could be absolutely devastating! To mitigate this risk, ensure that you apply the latest security patch provided by Microsoft for this vulnerability. Additionally, conduct regular system audits and limit access to essential personnel only to minimize potential exploitation. Your system’s defenses should be as tight as a drum! You've got this! Follow these steps and you'll keep your system secure and sound. 🛡️

The record
Technical detail
CVSS v3.1
7.8 · HIGH
Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
CVSS v4.0
Not supplied
EPSS
0.00489 · 41.1th percentile
Weakness
CWE-590 · Free of Memory not on the Heap
Published
2026-01-13T17:56Z
EPSS history
Timeline
  • 13 JAN 17:56Z
    Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability
    cvelistv5