Cisco Identity Services Engine Stored Cross-Site Scripting Vulnerability
Description
Cisco Identity Services Engine (ISE) contains a stored cross-site scripting (XSS) vulnerability in its web-based management interface. The vulnerability exists because the application fails to properly sanitize user-supplied input before writing it to log files that are later displayed in the administrative interface. An unauthenticated attacker can inject malicious JavaScript code by submitting specially crafted input that gets logged by the system. When an administrator views the affected log files or specific web pages, the malicious script executes in their browser session. This vulnerability requires user interaction, as an administrator must be convinced to click a malicious link or view a compromised log file.
Remediation
Apply the security patches provided by Cisco immediately by upgrading to a fixed version of Cisco Identity Services Engine. Refer to the Cisco Security Advisory (cisco-sa-20190109-ise-multi-xss) for specific version information and upgrade paths for your deployment.
Remediation steps:
1. Review the Cisco Security Advisory to identify the fixed software version appropriate for your ISE deployment
2. Back up your current ISE configuration before upgrading
3. Download the patched ISE software from Cisco's official download portal
4. Follow Cisco's upgrade procedures to install the fixed version
5. After upgrading, review and clear any suspicious log entries that may contain injected scripts
6. As an additional security measure, implement Content Security Policy (CSP) headers if supported in your version
If immediate patching is not possible, implement these temporary mitigations:
- Restrict access to the ISE management interface to trusted IP addresses only
- Educate administrators to avoid clicking on unsolicited links related to ISE
- Monitor log files for suspicious JavaScript or HTML content before viewing them in the web interface