PT-2026-32874 · Microsoft · Windows Ancillary Function Driver For Winsock+1

Published 2026-04-14 · Updated 2026-04-15 · CVE-2026-33100

Positive Technologies (AI Summary)

CVSS v3.1

7.0

High

Base vector

AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Windows Ancillary Function Driver for WinSock (affected versions not specified)

Description A use after free issue in the Windows Ancillary Function Driver for WinSock (AFD.sys) allows an authorized local attacker to elevate privileges on the system.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Use After Free

Weakness Enumeration

CWE-416

Related Identifiers

BDU:2026-05677

CVE-2026-33100

Affected Products

Windows

Windows Ancillary Function Driver For Winsock

References · 7

• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33100 · Vendor Advisory
• https://bdu.fstec.ru/vul/2026-05677 · Security Note
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-33100 · Security Note
• https://msrc.microsoft.com/update-guide/en-US/advisory/CVE-2026-33100 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-33100 · Security Note
• https://twitter.com/windowsforum/status/2044187495911334116 · Twitter Post
• https://twitter.com/CVEnew/status/2044358563477278868 · Twitter Post