CVE-2020-9858
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 · uneditedA dynamic library loading issue was addressed with improved path searching. This issue is fixed in Windows Migration Assistant 2.2.0.0 (v. 1A11). Running the installer in an untrusted directory may result in arbitrary code execution.
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 · high confidenceThis is a DLL hijacking vulnerability in Windows Migration Assistant 2.2.0.0 where the installer loads dynamic libraries without proper path validation. When executed from an untrusted directory, the installer may load malicious DLLs present in that directory, allowing arbitrary code execution with the installer's 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< 2.2.0.0CVSS 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
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:N/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 checksWork through these to decide whether this CVE applies to you.
-
Check if Windows Migration Assistant is installedOpen Control Panel > Programs and Features, or run 'Get-ItemProperty HKLM:\Software\Microsoft\Windows\CurrentVersion\Uninstall\* | Select-Object DisplayName, DisplayVersion' in PowerShell to list installed programsAffected if Apple Windows Migration Assistant appears in the installed programs list with a version below 2.2.0.0
-
Locate the Windows Migration Assistant installer executableSearch for files named 'WindowsMigrationAssistant.exe' or similar using File Explorer search or Get-ChildItem -Path C:\ -Recurse -Filter '*MigrationAssistant*.exe' in PowerShellAffected if The installer executable is found in a download directory, temp folder, or other untrusted location rather than a trusted system folder
-
Determine the exact version of the installed applicationRight-click the installed application in Programs and Features and select Properties, or right-click the installer executable and view the Details tab to see the File VersionAffected if The version displayed is lower than 2.2.0.0 or the version field is empty/unavailable
-
Verify the current installation pathLocate the installation directory (typically C:\Program Files\Apple\ or C:\Program Files (x86)\Apple\) and check for the presence of the Migration Assistant application filesAffected if The application is installed but originates from or has been run from an untrusted directory path
-
Check for recent execution from untrusted directoriesReview recent download folder contents, check Windows Event Viewer for Application logs around the time of migration assistant execution, or inspect browser download historiesAffected if Evidence shows the installer was run directly from a Downloads folder, Desktop, or network share without being copied to a trusted location first
A user is affected if Windows Migration Assistant version below 2.2.0.0 is installed and the installer has been or could be executed from an untrusted directory path.
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.
From vendor data2.2.0.0
Avoid running the Windows Migration Assistant installer from untrusted or download directories; copy it to a trusted location (e.g., a clean folder on the system drive) before execution. Ensure software is obtained from official sources only.
- Consultation2.0 h
- Implementation1.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,696.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-9858 — 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-2020-9858 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
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.
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.
- 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