CVE-2020-26067
📋 TL;DR
This vulnerability allows an authenticated attacker to inject malicious scripts into Cisco Webex Teams via crafted usernames, potentially stealing sensitive data from other users. It affects Cisco Webex Teams deployments with vulnerable versions. Users interacting with spaces containing malicious accounts are at risk.
💻 Affected Systems
- Cisco Webex Teams
📦 What is this software?
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Attacker steals session cookies or credentials, leading to account takeover and unauthorized access to sensitive team communications.
Likely Case
Attacker performs limited data theft from users viewing the malicious username, such as session tokens or personal information.
If Mitigated
Impact is minimal if patched; otherwise, web application firewalls or script-blocking browser extensions may reduce risk.
🎯 Exploit Status
Exploitation requires authenticated access and social engineering to lure victims; no public exploit code known.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Updated versions as per Cisco advisory; check specific release notes.
Vendor Advisory: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-webex-teams-xss-zLW9tD3
Restart Required: No
Instructions:
1. Access Cisco Webex Teams admin interface. 2. Check current version. 3. Apply the latest software update from Cisco. 4. Verify update completion via version check.
🧯 If You Can't Patch
- Restrict user account creation to trusted individuals only.
- Monitor logs for unusual username patterns or XSS attempts.
🔍 How to Verify
Check if Vulnerable:
Check Cisco Webex Teams version against the advisory; if prior to patched version, assume vulnerable.Check Version:
Not provided; typically via admin interface or vendor-specific commands.Verify Fix Applied:
Confirm version is updated to the patched release listed in the Cisco advisory.📡 Detection & Monitoring
Log Indicators:
- Log entries showing account creation with unusual characters or script-like usernames.
- Access logs to spaces with potential XSS payloads.
Network Indicators:
- HTTP requests containing malicious script tags in username parameters.
SIEM Query:
Example: 'webex teams username contains <script>' or similar pattern matching.