dbcve.org
Windows 10 1607Operating system · Microsoft

CVE-2026-45596

HIGH · 7.0 CVSS v3.1 Published 2026-06-09
Fix available
A fix is available. Upgrade to 10.0.14393.9234 / 10.0.17763.8880 or later.
See remediation →
72/100
Remediation priority · Elevated
Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Use after free in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

A use-after-free vulnerability exists in the Windows Ancillary Function Driver (AFD) for WinSock. This kernel-mode driver handles Winsock operations, and the UAF condition allows a locally authorized attacker to execute code with elevated privileges, potentially achieving local privilege escalation.

MitigationApply the relevant Microsoft Windows security update addressing this vulnerability in the AFD driver. Prioritize patching systems with local user access as the attack requires local access.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Windows 10 1607Operating system
Affected:< 10.0.14393.9234
Windows 10 1809Operating system
Affected:< 10.0.17763.8880
Windows 10 21h2Operating system
Affected:< 10.0.19044.7417
Windows 10 22h2Operating system
Affected:< 10.0.19045.7417
Windows 11 23h2Operating system
Affected:< 10.0.22631.7219
Windows 11 24h2Operating system
Affected:< 10.0.26100.8655
Windows 11 25h2Operating system
Affected:< 10.0.26200.8655
Windows 11 26h1Operating system
Affected:< 10.0.28000.2269

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
High
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check Windows build number
    Run 'winver' or 'systeminfo | findstr /B /C:"OS Version"' to obtain the full build number including the revision (e.g., 10.0.19045.7417)
    Affected if The build number is lower than any of the affected thresholds: 14393.9234 (1607), 17763.8880 (1809), 19044.7417 (21h2), 19045.7417 (22h2), 22631.7219 (23h2), 26100.8655 (24h2), 26200.8655 (25h2), or 28000.2269 (26h1)
  2. Confirm AFD driver is present
    Run 'driverquery /v | findstr afd' or check C:\Windows\System32\drivers\afd.sys exists
    Affected if The AFD driver file exists on the system (this is the vulnerable component)
  3. Verify local user access
    Review which user accounts have local logon rights using 'net user' or Local Security Policy (secpol.msc) under User Rights Assignment
    Affected if Multiple non-admin users have local access, as this is a local privilege escalation vulnerability

The system is affected if it runs any Windows 10/11 version with a build number below the threshold for its release, and the AFD driver is present (standard on all affected Windows installations with Winsock enabled).

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 10.0.14393.9234 / 10.0.17763.8880 / 10.0.19044.7417 or later
Fixed in 10.0.14393.923410.0.17763.888010.0.19044.7417
Interim mitigation

Apply the relevant Microsoft Windows security update addressing this vulnerability in the AFD driver. Prioritize patching systems with local user access as the attack requires local access.

Recommended fix High confidence

Upgrade to: Windows 10 1607 build 10.0.14393.9234+ | Windows 10 1809 build 10.0.17763.8880+ | Windows 10 21h2 build 10.0.19044.7417+ | Windows 10 22h2 build 10.0.19045.7417+ | Windows 11 23h2 build 10.0.22631.7219+ | Windows 11 24h2 build 10.0.26100.8655+ | Windows 11 25h2 build 10.0.26200.8655+ | W

  1. Identify the current Windows version by running 'winver' or 'systeminfo' in Command Prompt
  2. Determine which version family applies (Windows 10 1607, 1809, 21h2, 22h2, or Windows 11 23h2, 24h2, 25h2, 26h1)
  3. Open Windows Update Settings (Start > Settings > Update & Security > Windows Update)
  4. Click 'Check for updates' to download and install the latest security updates
  5. Alternatively, manually download and install the appropriate Cumulative Update from the Microsoft Update Catalog for your specific Windows version and build number
  6. Restart the system after updates are installed
  7. Verify the installed version matches or exceeds the fixed build number for your version family
Caveat Standard Windows update deployment; ensure compatibility testing is performed for critical line-of-business applications before broad deployment in enterprise environments

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Windows 10 1607 Scoped from the published advisory
  • Consultation4.0 h
  • Implementation2.0 h
  • Testing4.0 h
  • Review / QA2.0 h
12.0 hours of engineering $2,120
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,392.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-45596 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-45596 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data