cbcvebase.
CVE-2026-21240
published 2026-02-10

CVE-2026-21240: Time-of-check time-of-use (toctou) race condition in Windows HTTP.sys allows an authorized attacker to elevate privileges locally.

high7CVSS 3.1
AVLACHPRLUINSUCHIHAH
Time-of-check time-of-use (toctou) race condition in Windows HTTP.sys allows an authorized attacker to elevate privileges locally.

Affected

32 ranges· showing 25
VendorProductVersion rangeFixed in
microsoftwindows_10_1809< 10.0.17763.838910.0.17763.8389
microsoftwindows_10_21h2< 10.0.19044.693710.0.19044.6937
microsoftwindows_10_22h2< 10.0.19045.693710.0.19045.6937
microsoftwindows_10_version_1809>= 10.0.17763.0 < 10.0.17763.838910.0.17763.8389
microsoftwindows_10_version_21h2>= 10.0.19044.0 < 10.0.19044.693710.0.19044.6937
microsoftwindows_10_version_22h2>= 10.0.19045.0 < 10.0.19045.693710.0.19045.6937
microsoftwindows_11_23h2< 10.0.22631.664910.0.22631.6649
microsoftwindows_11_24h2< 10.0.26100.778110.0.26100.7781
microsoftwindows_11_25h2< 10.0.26200.778110.0.26200.7781
microsoftwindows_11_version_22h3>= 10.0.22631.0 < 10.0.22631.664910.0.22631.6649
microsoftwindows_11_version_23h2>= 10.0.22631.0 < 10.0.22631.664910.0.22631.6649
microsoftwindows_11_version_24h2>= 10.0.26100.0 < 10.0.26100.784010.0.26100.7840
microsoftwindows_11_version_25h2>= 10.0.26200.0 < 10.0.26200.784010.0.26200.7840
microsoftwindows_11_version_26h1>= 10.0.28000.0 < 10.0.28000.157510.0.28000.1575
microsoftwindows_server_2019< 10.0.17763.838910.0.17763.8389
microsoftwindows_server_2019>= 10.0.17763.0 < 10.0.17763.838910.0.17763.8389
microsoftwindows_server_2022< 10.0.20348.471110.0.20348.4711
microsoftwindows_server_2022>= 10.0.20348.0 < 10.0.20348.477310.0.20348.4773
microsoftwindows_server_2022_23h2< 10.0.25398.214910.0.25398.2149
microsoftwindows_server_2025< 10.0.26100.3231310.0.26100.32313
microsoftwindows_server_2025>= 10.0.26100.0 < 10.0.26100.3237010.0.26100.32370
msrcwindows_10_version_1809
msrcwindows_10_version_21h2
msrcwindows_10_version_22h2
msrcwindows_11_version_23h2