CVE-2021-34408
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 · uneditedThe Zoom Client for Meetings for Windows in all versions before version 5.3.2 writes log files to a user writable directory as a privileged user during the installation or update of the client. This could allow for potential privilege escalation if a link was created between the user writable directory used and a non-user writable directory.
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 Zoom Client for Meetings Windows installer (all versions before 5.3.2) writes log files to a user-writable directory while running with elevated privileges. This creates a symlink-based privilege escalation vector where an attacker could create a symbolic link from the log directory to a protected system location, causing the privileged installer to write to that protected location.
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< 5.3.2CVSS 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.
-
Verify Zoom Client for Meetings is installed on WindowsCheck for Zoom installation in Program Files (e.g., C:\Program Files\Zoom\bin\Zoom.exe) or look for Zoom entry in Add/Remove Programs.Affected if Zoom Client for Meetings is installed on Windows.
-
Determine installed Zoom versionRight-click Zoom.exe, select Properties, then view the Details tab for Product Version. Alternatively, open Zoom and click the user icon > Check for Updates to see the current version.Affected if The displayed version number is less than 5.3.2.
-
Confirm Windows platformVerify the affected system is running Windows. This vulnerability applies only to the Windows client installer.Affected if The operating system is Windows.
A Windows user is affected if Zoom Client for Meetings version is below 5.3.2, as the installer writes privileged log files to a user-writable location creating a symlink escalation vector.
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 · scoped5.3.2
Upgrade Zoom Client for Meetings to version 5.3.2 or later to resolve the insecure log file placement during installation or update.
5.3.2 or later
- Open the Zoom Client for Meetings on your Windows machine
- Click on your profile picture or account icon in the top-right corner
- Select 'Check for Updates' from the menu
- If an update is available, download and install version 5.3.2 or later
- Alternatively, download the installer directly from the official Zoom website (explore.zoom.us)
- Run the installer and follow the prompts to complete the upgrade
- Restart the Zoom client after the update completes
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation6.0 h
- Testing3.0 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 $3,984.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-34408 — 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-2021-34408 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