Windows 10 21h2Operating system · Microsoft

CVE-2026-50364

HIGH · 7.3 CVSS v3.1 Published 2026-07-14
Fix available
A fix is available. Upgrade to 10.0.19044.7548 / 10.0.19045.7548 or later.
See remediation →
73/100
Remediation priority · Elevated
5 weeks old

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
Improper link resolution before file access ('link following') in Windows Server Backup allows an authorized attacker to elevate privileges locally.

In the news

Third-party coverage
Trending covered by 1 outlet this week · latest 1mo ago

Surfaced from public web coverage — external links open in a new tab.

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

This is a link following (symlink/junction point) vulnerability in Windows Server Backup where the software fails to properly validate symbolic links or junction points before accessing files during backup operations. An authorized local attacker can exploit this to manipulate file access patterns and elevate privileges to higher permissions on the affected Windows Server system.

MitigationApply Microsoft security updates for Windows Server Backup when released. In the interim, limit administrative access, monitor for unauthorized symlink/junction creation in backup directories, and restrict backup folder permissions to trusted administrators only.

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 21h2Operating system
Affected:< 10.0.19044.7548
Windows 10 22h2Operating system
Affected:< 10.0.19045.7548
Windows 11 24h2Operating system
Affected:< 10.0.26100.8875
Windows 11 25h2Operating system
Affected:< 10.0.26200.8875
Windows 11 26h1Operating system
Affected:< 10.0.28000.2269< 10.0.28000.2525

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
Low
Privileges
Low
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:R/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 version and build number
    Run 'winver' or 'systeminfo | findstr /B /C:"OS Name" /C:"OS Version"' to get the exact Windows version and build. Compare against the affected version ranges: Windows 10 21h2 < 10.0.19044.7548, Windows 10 22h2 < 10.0.19045.7548, Windows 11 24h2 < 10.0.26100.8875, Windows 11 25h2 < 10.0.26200.8875, Windows 11 26h1 < 10.0.28000.2269 or < 10.0.28000.2525
    Affected if The installed Windows version falls within any of the affected version ranges listed
  2. Verify Windows Server Backup feature is enabled
    Open 'Services' console (services.msc) and check if 'Windows Server Backup' service status is Running or if the feature is installed. Alternatively, run 'wbadmin get disks' to test if backup commands are functional
    Affected if Windows Server Backup service exists and is accessible on the system
  3. Inspect backup destination directories for symlinks or junction points
    Use 'cmd' to navigate to your configured backup destination folders (commonly C:\WindowsImageBackup, D:\Backup, or custom locations). Run 'dir /AL /S' to list all alternate data stream links and junction points recursively
    Affected if Unexpected symlinks or junction points exist in backup directories pointing to sensitive system locations
  4. Check backup folder permissions for unauthorized modification
    Right-click backup directories, go to Properties > Security, and verify that only trusted administrator accounts have Write or Full Control permissions. Run 'icacls <backup_path>' to enumerate effective permissions
    Affected if Non-administrator users or untrusted accounts have Write or Modify permissions on backup directories

A system is affected if it runs a vulnerable Windows version in the specified ranges AND has Windows Server Backup feature enabled, with an attacker able to create symlinks/junction points in backup directories.

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 10.0.19044.7548 / 10.0.19045.7548 / 10.0.26100.8875 or later
Fixed in 10.0.19044.754810.0.19045.754810.0.26100.8875
Interim mitigation

Apply Microsoft security updates for Windows Server Backup when released. In the interim, limit administrative access, monitor for unauthorized symlink/junction creation in backup directories, and restrict backup folder permissions to trusted administrators only.

Recommended fix Moderate confidence

Apply Microsoft security update from Windows Update (KB reference needed from MSRC)

  1. Check current Windows build version by running `winver` or `systeminfo | findstr /B /C:"OS Name" /C:"OS Version"`
  2. Identify your Windows version (10 21h2, 10 22h2, 11 24h2, 11 25h2, or 11 26h1) from the build number
  3. Apply the appropriate Microsoft security update for this vulnerability from Windows Update or Microsoft Update Catalog
  4. After installation, verify the build number matches or exceeds the fixed version: 10.0.19044.7548 (Win10 21h2), 10.0.19045.7548 (Win10 22h2), 10.0.26100.8875 (Win11 24h2), 10.0.26200.8875 (Win11 25h2), or 10.0.28000.2525 (Win11 26h1)
  5. Restart the system as prompted to complete the update
Caveat Standard Windows security update; may require restart

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

Fix this in Windows 10 21h2 Scoped from the published advisory
  • Consultation4.0 h
  • Implementation2.0 h
  • Testing6.0 h
  • Review / QA3.0 h
15.0 hours of engineering $2,600
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,160.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-50364 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-50364 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