CVE-2026-84009

MEDIUMCVSS 4.7

Description

Time-of-check time-of-use (toctou) race condition in Windows Projected File System allows an authorized attacker to perform tampering locally.

Timeline

Published:October 13th, 2026 7:20 PM

Last modified:October 19th, 2026 7:16 PM

CVSS Scoring

CVSS v3: 4.7 (MEDIUM)

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N

Affected Software

From NVD CPE configuration data

Vendors

microsoft

Products

windows_10_1809windows_10_21h2windows_10_22h2windows_11_23h2windows_11_24h2windows_11_25h2windows_11_26h1windows_11_26h2windows_server_2019windows_server_2022windows_server_2025

Weaknesses (CWE)

CWE-367

References & Reports

Advisories, patches, and third-party reports

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-84009Vendor Advisory

Source: NIST NVD · Data may lag official sources by up to one minute