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CVE-2026-21222

Windows Kernel Information Disclosure Vulnerability

No known exploitation. EPSS puts it in the 48th percentile. Fixed versions are out.

CVSS 3.15.5MediumEPSS percentile48th0.6% chance in 30 daysCISA KEVNot listedNo confirmed exploitation
No public exploit knownFix5 products8 fixed builds listed below

Published Updated Sources: CVE.org, NVD, BDU

NVD CVE.org

What to do

Find your product and version, then upgrade to the build on the right.

  • Microsoft Windows Server 2012 R2Affected: ≥ 6.3.9600.0, < 6.3.9600.23022Upgrade to: 6.3.9600.23022Stated by: CVE record
  • Microsoft Windows Server 2016Affected: ≥ 10.0.14393.0, < 10.0.14393.8868Upgrade to: 10.0.14393.8868Stated by: CVE record
  • Microsoft Windows 10 Version 1607Affected: ≥ 10.0.14393.0, < 10.0.14393.8868Upgrade to: 10.0.14393.8868Affected: ≥ 10.0.17763.0, < 10.0.17763.8389Upgrade to: 10.0.17763.8389Affected: ≥ 10.0.19044.0, < 10.0.19044.6937Upgrade to: 10.0.19044.6937Affected: ≥ 10.0.19045.0, < 10.0.19045.6937Upgrade to: 10.0.19045.6937Stated by: CVE record
  • Microsoft Windows Server 2025Affected: ≥ 10.0.26100.0, < 10.0.26100.32370Upgrade to: 10.0.26100.32370Stated by: CVE record
  • Microsoft Windows 11 version 22H3Affected: ≥ 10.0.22631.0, < 10.0.22631.6649Upgrade to: 10.0.22631.6649Affected: ≥ 10.0.26100.0, < 10.0.26100.7840Upgrade to: 10.0.26100.7840Stated by: CVE record

Versions as the sources state them. 2 more products have version data. Full version matrix after sign-in

Check it yourselfA free OpenVAS check exists for this CVE. Run it against your hosts.Is your organisation exposed?Request an assessment to establish which checks fit your systems.

What it is

From the CVE record

Insertion of sensitive information into log file in Windows Kernel allows an authorized attacker to disclose information locally.

In plain language

No plain-language summary for this CVE yet.

Exploitation

Where each signal puts this CVE on the scale from published to confirmed exploited.

EPSS48th
CISA KEV

Not in the catalog. CISA has not confirmed exploitation.

Public exploits

No public exploit or proof of concept found in the sources we track.

EPSS

0.6% chance of exploitation activity in the next 30 days, which ranks it in the 48th percentile of scored CVEs.

Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.

Lifecycle

6 events over 135 days, from the signal feeds we watch.

  1. OpenVAS check added
  2. Patch availablerecord updated
  3. Publishedweakness classified, att&ck mapped

Affected products

And 38 more affected products. See all after sign-in

Technical detail

CVSS 3.1 vector

Open in the CVSS calculator

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Scored 5.5 by NVD.

How it is reached

  • Attack Vector LocalRequires local access to the vulnerable system (e.g. local login, malicious file)
  • Attack Complexity LowNo special conditions — the attack can be reliably reproduced
  • Privileges Required LowRequires basic user-level privileges
  • User Interaction NoneNo user interaction needed — fully automated exploitation

Scope

  • Scope UnchangedImpact is limited to the vulnerable component itself

Impact if exploited

  • Confidentiality HighTotal information disclosure — all data in the component is compromised
  • Integrity NoneNo integrity impact
  • Availability NoneNo availability impact

Weaknesses

ATT&CK techniques

Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.

Sources

References in the record

In the news

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