CVE-2026-21250: Microsoft Windows 11 Version 24H2 · Untrusted Pointer Dereference
Affects Microsoft Windows 11 Version 24H2Source CVE Database V5
Public exploit available (Exploit-DB) · CVSS 7.8 High : upgrade to 10.0.26100.7840 as a priority.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 1.1% chance of exploitation in 30 days – higher than 65% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 10.0.26100.7840, 10.0.26200.7840, 10.0.28000.1575 +2
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:CExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 10 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: evidence found.
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE ID reserved
by Microsoft Corporation
, 61 days before disclosure
CVE published
on cve.org
, t = 0
In Threat Radar
record ingested
, 25 minutes after disclosure
First Exploit-DB entry (opens in a new tab)
Windows 11 24H2 - Local Privilege Escalation
, 83 days after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| MicrosoftWindows 11 Version 24H2 | Affected
| Fixed in
|
| MicrosoftWindows 11 Version 25H2 | Affected
| Fixed in
|
| MicrosoftWindows 11 version 26H1 | Affected
| Fixed in
|
| MicrosoftWindows 11 Version 26H1 | Affected
| Fixed in
|
| MicrosoftWindows Server 2022, 23H2 Edition (Server Core installation) | Affected
| Fixed in
|
| MicrosoftWindows Server 2025 | Affected
| Fixed in
|
AI-suggested
An official fix is available from Microsoft. Users and administrators should apply the security update provided in the Microsoft advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-21250 to remediate this vulnerability. No additional mitigation steps are indicated by the vendor.
Description
Untrusted pointer dereference in Windows HTTP.sys allows an authorized attacker to elevate privileges locally.