dbcve.org
Webex MeetingsApplication · Cisco

CVE-2026-20233

MEDIUM · 6.1 CVSS v3.1 Published 2026-06-03
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
68/100
Remediation priority · Elevated
Remotely reachable No privileges

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
A vulnerability in the web-based user interface of Cisco Webex Meetings could have allowed an unauthenticated, remote attacker to conduct a cross-site scripting (XSS) attack. Cisco has addressed this vulnerability in the Webex Meetings service, and no customer action is needed. This vulnerability existed because of insufficient validation of user input. Prior to this vulnerability being addressed, an attacker could have exploited this vulnerability by persuading a user to follow a malicious link. A successful exploit could have allowed the attacker to execute arbitrary script code in the browser of the targeted user or access sensitive, browser-based information.

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 confidence

Cross-site scripting (XSS) vulnerability in Cisco Webex Meetings web interface due to insufficient input validation. An unauthenticated attacker could inject malicious scripts via a crafted link, allowing execution of arbitrary code in users' browsers or access to sensitive browser-based information.

MitigationNo action required. Cisco has already addressed this vulnerability in the Webex Meetings service; the patch was applied server-side.

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 MeetingsApplication
Affected:= 39.6.0= 39.7.0= 39.7.4= 39.7.7= 39.8.0= 39.8.2= 39.8.3= 39.8.4= 39.9.0= 39.9.1= 39.10.0= 39.11.0

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
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

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. Identify your Cisco Webex Meetings version
    Log into the Webex Meetings site and locate the version number, typically displayed in the footer of the web interface, in the Help > About section, or in the Administration portal under site information
    Affected if The version displayed matches any of the following: 39.6.0, 39.7.0, 39.7.4, 39.7.7, 39.8.0, 39.8.2, 39.8.3, 39.8.4, 39.9.0, 39.9.1, 39.10.0, or 39.11.0
  2. Confirm web UI is accessible
    Verify that the Cisco Webex Meetings web-based user interface is accessible to users within your organization by attempting to reach your organization's Webex URL (typically at webex.com or your custom domain)
    Affected if The web interface is accessible and the version identified in step 1 is in the affected list
  3. Review web access logs for suspicious URL patterns
    Examine web server or proxy logs for requests to Webex Meetings that contain unusual script tags, javascript:, or other XSS payloads in URL parameters (such as ?url=, ?redirect=, or query string parameters)
    Affected if Log entries show crafted URLs containing script injection attempts targeting the Webex interface
  4. Check for recent XSS exploitation indicators
    Review browser-based security logs, SIEM alerts, or Webex admin audit logs for any incidents or warnings related to XSS attempts, unauthorized script execution, or user reports of unexpected browser behavior after clicking Webex links
    Affected if Any alerts, logs, or user reports indicate successful or attempted XSS exploitation in the Webex web interface

Your environment is affected if your Cisco Webex Meetings web interface version matches any of the 12 listed affected versions (39.6.0 through 39.11.0), since the vulnerability exists in the web UI itself and requires no special configuration to be exploitable beyond a user clicking a crafted URL.

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
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

No action required. Cisco has already addressed this vulnerability in the Webex Meetings service; the patch was applied server-side.

Recommended fix High confidence
  1. No customer action is required. Cisco has addressed this vulnerability in the Webex Meetings service through a server-side fix.

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

Fix this in Webex Meetings Scoped from the published advisory
  • Consultation1.0 h
  • Testing1.0 h
  • Review / QA1.0 h
3.0 hours of engineering $750
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,200.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-20233 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2026-20233 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