CVE-2021-31776
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 · uneditedAviatrix VPN Client before 2.14.14 on Windows has an unquoted search path that enables local privilege escalation to the SYSTEM user, if the machine is misconfigured to allow unprivileged users to write to directories that are supposed to be restricted to administrators.
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 confidenceThe Aviatrix VPN Client for Windows versions prior to 2.14.14 contains an unquoted service path vulnerability that allows local privilege escalation to SYSTEM privileges. Attackers can place a malicious executable in a directory along the service path that contains a space, causing the service to execute the attacker's code with elevated 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< 2.14.14CVSS 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.
-
Check if Aviatrix VPN Client is installedOpen Windows Registry Editor and navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall or look for the Aviatrix VPN Client in Add/Remove Programs. Alternatively, check for the presence of C:\Program Files\Aviatrix or C:\Program Files (x86)\Aviatrix directories.Affected if The Aviatrix VPN Client directory or registry entry exists on the system.
-
Identify installed Aviatrix VPN Client versionCheck the version in the Windows Registry under the Aviatrix uninstall key, or right-click the aviatrix.exe file in the installation directory, select Properties, and view the Details tab for the File Version.Affected if The installed version is lower than 2.14.14.
-
Identify the Aviatrix VPN serviceOpen Services (services.msc), locate the Aviatrix VPN service, right-click and select Properties, and note the path to the executable shown in 'Path to executable'.Affected if The service executable path contains spaces and is not enclosed in quotes.
-
Verify service path vulnerabilityExamine the service's executable path. If it is something like C:\Program Files\Aviatrix\VPN Client\vpnclient.exe without quotes, and an attacker can place a malicious executable in a subdirectory with a space (e.g., C:\Program.exe), the vulnerability exists.Affected if The service path contains unquoted spaces and the filesystem permissions allow unprivileged users to write to directories along the path.
The system is affected if Aviatrix VPN Client version is below 2.14.14 AND the service path contains unquoted spaces with writable directories along that 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 data2.14.14
Upgrade Aviatrix VPN Client to version 2.14.14 or later, and audit filesystem permissions on system directories to ensure unprivileged users cannot write to administrator-restricted directories.
- Consultation2.0 h
- Implementation2.0 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 $1,984.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-31776 — 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-2021-31776 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