CVE-2026-83939: Untrusted pointer dereference in Windows Secure Kernel Mode allows an authorized attacker to elevate privilege

Q: How do I fix CVE-2026-83939?

windows 11 26h1: upgrade to 10.0.28000.2954. Exact commands for each OS are on this page.

Q: Is CVE-2026-83939 being exploited?

CVE-2026-83939 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-83939 affect?

CVE-2026-83939 affects windows 11 26h1. Severity is high (CVSS 8.2). Untrusted pointer dereference in Windows Secure Kernel Mode allows an authorized attacker to elevate privileges locally.

Q: How urgent is CVE-2026-83939?

Priority 41/100. High severity; On your watchlist

This month

HIGH 8.2WATCHLISTUPGRADE

CVE-2026-83939 is a high-severity flaw (CVSS 8.2) affecting windows 11 26h1. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Untrusted pointer dereference in Windows Secure Kernel Mode 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	8.2 (High)
Attack vector	Local
Attack complexity	Low
Privileges needed	High
User interaction	None
EPSS exploit chance	0.3% (top 72%)
CISA exploited list	No
Weakness	CWE-822
Published	2026-09-08
Last modified	2026-09-10

Publisher (CNA): Microsoft Corporation · Vendor: microsoft

Last updated 2026-09-10 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-09-08 18:21 UTCPublished CVE record published
2026-09-10 15:00 UTCUpdated Record last modified

microsoft windows 11 26h1 UPGRADE

Affected: < 10.0.28000.2954

Fixed in: 10.0.28000.2954

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.

Quick answers

How do I fix CVE-2026-83939?

windows 11 26h1: upgrade to 10.0.28000.2954. Exact commands for each OS are on this page.

Is CVE-2026-83939 being exploited?

CVE-2026-83939 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-2026-83939 affect?

CVE-2026-83939 affects windows 11 26h1. Severity is high (CVSS 8.2). Untrusted pointer dereference in Windows Secure Kernel Mode allows an authorized attacker to elevate privileges locally.

How urgent is CVE-2026-83939?

Priority 41/100. High severity; On your watchlist

Software pages

Windows vulnerabilities

Related CVEs

CVE-2026-26179 HIGH 7.8 UPGRADE UPGRADE Double free in Windows Kernel allows an authorized attacker to elevate privileges locally.
CVE-2026-32152 HIGH 7.8 UPGRADE UPGRADE Use after free in Desktop Window Manager allows an authorized attacker to elevate privileges locally.
CVE-2026-27907 HIGH 7.8 UPGRADE UPGRADE Integer underflow (wrap or wraparound) in Windows Storage Spaces Controller allows an authorized attacker to e
CVE-2026-32218 MEDIUM 5.5 UPGRADE UPGRADE Insertion of sensitive information into log file in Windows Kernel allows an authorized attacker to disclose i
CVE-2026-25184 HIGH 7.0 UPGRADE UPGRADE Concurrent execution using shared resource with improper synchronization ('race condition') in Applocker Filte

References

← Back to latest CVEs