Webex Meetings DesktopApplication · Cisco
CVE-2021-1536
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 vulnerability in Cisco Webex Meetings Desktop App for Windows, Cisco Webex Meetings Server, Cisco Webex Network Recording Player for Windows, and Cisco Webex Teams for Windows could allow an authenticated, local attacker to perform a DLL injection attack on an affected device. To exploit this vulnerability, the attacker must have valid credentials on the Windows system. This vulnerability is due to incorrect handling of directory paths at run time. An attacker could exploit this vulnerability by inserting a configuration file in a specific path in the system, which can cause a malicious DLL file to be loaded when the application starts. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of another user account.
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 injection vulnerability in Cisco Webex desktop applications for Windows. The flaw stems from improper handling of directory paths at runtime, allowing an authenticated attacker with local system access to place a malicious configuration file in a specific path. When the application starts, it loads a malicious DLL from this path, enabling arbitrary code execution with the privileges of the targeted user account.
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
Webex Meetings DesktopApplication
all versions
Webex Meetings OnlineApplication
all versions
Webex Meetings ServerApplication
= 4.0
Webex Network Recording PlayerApplication
all versions
Webex TeamsApplication
= 3.0.15485.0CVSS 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.
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Identify installed Webex productsOpen Programs and Features (appwiz.cpl) or check typical installation directories such as C:\Program Files\Webex or C:\Users\%username%\AppData\Local\Webex for Cisco Webex software components including Webex Meetings Desktop, Webex Teams, and Webex Network Recording PlayerAffected if Any Cisco Webex product listed in the affected products is found installed on the system
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Check installed version against affected rangesRight-click the installed Webex application executable, select Properties, then view the Details tab to find the File Version. Compare this version to the affected ranges: Cisco Webex Meetings Server version 4.0, Cisco Webex Teams version 3.0.15485.0, or any version for Cisco Webex Meetings Desktop and Cisco Webex Network Recording PlayerAffected if The installed version matches 4.0 for Webex Meetings Server, 3.0.15485.0 for Webex Teams, or is any version for Webex Meetings Desktop or Webex Network Recording Player
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Inspect application directories for unauthorized configuration filesCheck the Webex installation directory and runtime directories for unexpected or newly created configuration files (such as config.ini, config.xml, or similar) that were not placed there by the installation process. Look for files with modified timestamps or suspicious namesAffected if Unauthorized or unexpected configuration files are present in Webex application directories
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Verify filesystem permissions on Webex directoriesRight-click the Webex installation folder, select Properties, go to the Security tab, and verify which users and groups have Write or Modify permissions. Check if untrusted users have write access to the application directoryAffected if Users without administrative privileges or untrusted accounts have Write or Modify permissions to Webex installation directories
If any Cisco Webex product from the affected list is installed and the application directories are writable by untrusted users, the environment is vulnerable to DLL injection via malicious configuration file placement.
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 dataApply the vendor-supplied patches from Cisco for all affected Webex products. Additionally, restrict filesystem permissions on application directories to prevent unauthorized users from inserting configuration or DLL files, and monitor for suspicious DLL loading activity.
Fix this in Webex Meetings Desktop
Scoped from the published advisory
- Consultation2.0 h
- Implementation3.0 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 $2,272.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-1536 — 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-2021-1536 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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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