CVE-2026-20111
📋 TL;DR
This vulnerability allows an authenticated attacker with administrative credentials to inject malicious scripts into Cisco Prime Infrastructure's web interface, potentially compromising other users' sessions or stealing sensitive data. It affects systems running vulnerable versions of Cisco Prime Infrastructure with the web-based management interface enabled.
💻 Affected Systems
- Cisco Prime Infrastructure
⚠️ 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
An attacker could steal administrative credentials, hijack user sessions, or perform unauthorized actions on the system, leading to full compromise of the management interface.
Likely Case
An attacker with valid admin access could execute stored XSS to capture session cookies or redirect users to malicious sites, potentially escalating privileges or exfiltrating data.
If Mitigated
With proper input validation and output encoding, the risk is reduced to minimal, preventing script execution even if malicious input is inserted.
🎯 Exploit Status
Exploitation requires authenticated admin access and knowledge of vulnerable input fields; stored XSS can be triggered by other users viewing the malicious content.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Refer to the Cisco advisory for patched versions; typically requires updating to a fixed release.
Vendor Advisory: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-pi-xss-bYeVKCD
Restart Required: Yes
Instructions:
1. Review the Cisco advisory for affected versions. 2. Download and apply the recommended patch or upgrade to a fixed version. 3. Restart the Cisco Prime Infrastructure service or system as required. 4. Verify the fix by testing input validation in the web interface.
🔧 Temporary Workarounds
Input Validation and Sanitization
allImplement server-side input validation and output encoding to prevent XSS attacks.
Not applicable; requires code changes or configuration adjustments.
Restrict Admin Access
allLimit administrative access to trusted users and networks to reduce attack surface.
Configure firewall rules to restrict access to the management interface from specific IPs.
🧯 If You Can't Patch
- Disable the web-based management interface if not required, using CLI or alternative management methods.
- Implement web application firewalls (WAF) to filter and block XSS payloads targeting the vulnerable fields.
🔍 How to Verify
Check if Vulnerable:
Check the Cisco Prime Infrastructure version against the advisory; if running an affected version and the web interface is enabled, it is vulnerable.Check Version:
Log into Cisco Prime Infrastructure and navigate to Admin > System > Software Updates, or use CLI commands specific to the platform (e.g., 'show version').Verify Fix Applied:
After patching, verify the version is updated and test input fields in the web interface for proper sanitization (e.g., by attempting to inject script tags).📡 Detection & Monitoring
Log Indicators:
- Look for unusual admin login attempts or POST requests with script-like payloads to input fields in web server logs.
Network Indicators:
- Monitor for HTTP requests containing XSS patterns (e.g., <script> tags) to the management interface endpoints.
SIEM Query:
Example: source="web_logs" AND (url="*input_field*" AND payload="*<script>*")