CVE-2026-21250
Windows HTTP.sys Elevation of Privilege Vulnerability
Untrusted pointer dereference in Windows HTTP.sys allows an authorized attacker to elevate privileges locally.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Windows HTTP.sys Elevation of Privilege Vulnerability
Untrusted pointer dereference in Windows HTTP.sys allows an authorized attacker to elevate privileges locally.
- Record
CVE-2026-21250- CVSS 3.1
- 7.8 High
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 - Weakness
- CWE-822
- Updated
- 2026-11-02
EUVDEUVD-2026-7321
Untrusted pointer dereference in Windows HTTP.sys allows an authorized attacker to elevate privileges locally.
- Record
EUVD-2026-7321- CVSS 3.1
- 7.8 High
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 - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-xmfc-7rh5-84qx
Untrusted pointer dereference in Windows HTTP.sys allows an authorized attacker to elevate...
Untrusted pointer dereference in Windows HTTP.sys allows an authorized attacker to elevate privileges locally.
- Record
GHSA-xmfc-7rh5-84qx- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-822
- Updated
- 2026-11-02
NVD
Untrusted pointer dereference in Windows HTTP.sys allows an authorized attacker to elevate privileges locally.
- Record
CVE-2026-21250- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-822
- Updated
- 2026-11-02
Affected products
- microsoft windows 11 version 24h2
- microsoft windows 11 version 25h2
- microsoft windows 11 version 26h1
- microsoft windows server 2022, 23h2 edition (server core installation)
- microsoft windows server 2025
- microsoft windows server 2025 (server core installation)
- microsoft windows 11 24h2
- microsoft windows 11 25h2
- microsoft windows server 2022 23h2
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| Exploit-DB | Windows 11 24H2 - Local Privilege Escalation | 2026-05-04 |
| PoC in GitHub | kaleth4/CVE-2026-21250 | 2026-05-04 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, Exploit-DB, GitHub Advisories, NVD, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-21250 is a high vulnerability (CVSS 7.8) in Microsoft Windows 11 Version 24h2, published February 10, 2026. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 1.09%, the 65th percentile. No source names a fixed version.