PatchTheCVECVE-2026-26165: Use after free in Windows Shell allows an authorized attacker to elevate privileges locally.
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Routine
HIGH 7.0WATCHLISTUPGRADEUPGRADEUPGRADE
CVE-2026-26165 is a high-severity flaw (CVSS 7.0) affecting windows 11 23h2, windows 11 24h2, windows 11 25h2. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Use after free in Windows Shell allows an authorized attacker to elevate privileges locally.
Why this priority
- High severity
- On your watchlist
A fixed release or distro patch exists.
Risk facts
| CVSS score | 7.0 (High) |
| Attack vector | Local |
| Attack complexity | High |
| Privileges needed | Low |
| User interaction | None |
| EPSS exploit chance | 0.3% (top 83%) |
| CISA exploited list | No |
| Weakness | CWE-416 |
| Published | 2026-04-14 |
| Last modified | 2026-10-26 |
Publisher (CNA): Microsoft Corporation · Vendor: microsoft
Last updated 2026-10-26 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
microsoft windows 11 23h2 UPGRADE
Affected: < 10.0.22631.6936
Fixed in: 10.0.22631.6936
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
microsoft windows 11 24h2 UPGRADE
Affected: < 10.0.26100.8246
Fixed in: 10.0.26100.8246
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
microsoft windows 11 25h2 UPGRADE
Affected: < 10.0.26200.8246
Fixed in: 10.0.26200.8246
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
microsoft windows 11 26h1 UPGRADE
Affected: < 10.0.28000.1836
Fixed in: 10.0.28000.1836
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
microsoft windows server 2022 UPGRADE
Affected: < 10.0.20348.5020
Fixed in: 10.0.20348.5020
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
microsoft windows server 2022 23h2 UPGRADE
Affected: < 10.0.25398.2274
Fixed in: 10.0.25398.2274
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-26165?
windows 11 23h2: upgrade to 10.0.22631.6936; windows 11 24h2: upgrade to 10.0.26100.8246; windows 11 25h2: upgrade to 10.0.26200.8246. Exact commands for each OS are on this page.
Is CVE-2026-26165 being exploited?
CVE-2026-26165 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-26165 affect?
CVE-2026-26165 affects windows 11 23h2, windows 11 24h2, windows 11 25h2. Severity is high (CVSS 7.0). Use after free in Windows Shell allows an authorized attacker to elevate privileges locally.
How urgent is CVE-2026-26165?
Priority 34/100. High severity; On your watchlist
Software pages
Windows vulnerabilities · Windows Server vulnerabilities
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