CVE-2026-24293
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 · uneditedNull pointer dereference 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 confidenceA null pointer dereference vulnerability exists in the Windows Ancillary Function Driver (AFD) for WinSock. This kernel-mode driver flaw allows a locally authorized attacker to exploit the dereference of an uninitialized or null pointer to achieve privilege escalation from a lower privilege context to elevated (SYSTEM) privileges.
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< 10.0.19044.7058< 10.0.19045.7058< 10.0.22631.6783< 10.0.26100.7979< 10.0.26200.7979< 10.0.28000.1719< 10.0.20348.4830< 10.0.25398.2207CVSS 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
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/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 checksWork through these to decide whether this CVE applies to you.
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Identify Windows versionRun 'winver' or 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' to determine the exact Windows build numberAffected if The build number falls below the patched version for your Windows release (e.g., < 10.0.19044.7058 for Win10 21h2, < 10.0.22631.6783 for Win11 23h2, etc.)
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Check AFD driver file versionRun 'Get-Item C:\Windows\System32\afd.sys | Select-Object VersionInfo' in PowerShell to retrieve the AFD.sys file versionAffected if The file version is older than the patched version corresponding to your Windows build (compare the FileVersion string to the threshold for your release)
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Query AFD driver via driver listRun 'driverquery /v | findstr AFD' or 'Get-WmiObject Win32_PnPSignedDriver | Where-Object {$_.DeviceName -like "*AFD*"} | Select-Object DeviceName, DriverVersion, DriverDate'Affected if The reported driver version is below the security update version for your Windows version
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Confirm kernel patch protection statusRun 'reg query "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" /v FeatureSettingsOverride' to check if kernel protections are enabled (value 0 typically means protections on)Affected if The system lacks standard kernel protections that may mitigate null pointer dereference exploitation (this is a secondary check; primary detection is version-based)
You are affected if your Windows build number or AFD.sys version is below the patched threshold for your specific Windows release and edition.
Generated from the published advisory. Verify against your own configuration.
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 · scoped10.0.19044.705810.0.19045.705810.0.20348.4830
Apply the Microsoft security update for CVE-2026-24293 via Windows Update or enterprise patch management systems. Validate that the AFD driver version has been updated to the patched version and confirm no regressions in network stack functionality.
April 2025 Security Updates (KB5055527 or corresponding update for your Windows version)
- Identify the current Windows version and build number by running 'winver' or 'systeminfo' in Command Prompt
- Determine which version band your system falls into (21h2, 22h2, 23h2, 24h2, 25h2, 26h1, Server 2022, or Server 2022 23h2)
- Open Windows Settings > Update & Security > Windows Update
- Click 'Check for updates' to download and install the April 2025 security updates
- Alternatively, manually download the update from Microsoft Update Catalog based on your specific Windows version and architecture
- Restart the system after the update installation completes
- Verify the installed build number matches or exceeds the fixed version for your release channel
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation2.0 h
- Testing6.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,552.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-24293 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-24293 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- 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