CVE-2026-21240

CWE-3675 documents5 sources
Severity
7.0HIGH
EPSS
0.0%
top 92.21%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
20
Microsoft Windows 10 Version 1809Microsoft Windows 10 Version 21h2Microsoft Windows 10 Version 22h2+17 more
Timeline
PublishedFeb 10

Description

Time-of-check time-of-use (toctou) race condition in Windows HTTP.sys allows an authorized attacker to elevate privileges locally.

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitability: 1.8 | Impact: 5.9

Affected Packages20 packages

▶NVDmicrosoft/windows< 10.0.17763.8389+3
▶NVDmicrosoft/windows_10_1809< 10.0.17763.8389
▶NVDmicrosoft/windows_10_21h2< 10.0.19044.6937
▶NVDmicrosoft/windows_10_22h2< 10.0.19045.6937
▶NVDmicrosoft/windows_11_23h2< 10.0.22631.6649

🔴Vulnerability Details

2
GHSA
GHSA-56fh-gxc8-3p64: Time-of-check time-of-use (toctou) race condition in Windows HTTP↗2026-02-10
▶
CVEList
Windows HTTP.sys Elevation of Privilege Vulnerability↗2026-02-10
▶

📋Vendor Advisories

1
Microsoft
Windows HTTP.sys Elevation of Privilege Vulnerability↗2026-02-10
▶

🕵️Threat Intelligence

1
Wiz
CVE-2026-21240 Impact, Exploitability, and Mitigation Steps | Wiz↗
▶
CVE-2026-21240 (HIGH CVSS 7) | Time-of-check time-of-use (toctou) | cvebase.io