CVE-2021-35493
📋 TL;DR
This CVE describes stored and reflected cross-site scripting (XSS) vulnerabilities in TIBCO WebFOCUS components that allow low-privileged attackers to trick legitimate users into executing malicious scripts. The attack requires social engineering and user interaction but can target both the affected system and the victim's local system. Affected systems include TIBCO WebFOCUS Client, Installer, and Reporting Server versions 8207.27.0 and below.
💻 Affected Systems
- TIBCO WebFOCUS Client
- TIBCO WebFOCUS Installer
- TIBCO WebFOCUS Reporting Server
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of user sessions, credential theft, installation of malware on victim systems, and potential lateral movement within the network.
Likely Case
Session hijacking, credential theft, and unauthorized actions performed in the context of authenticated users.
If Mitigated
Limited impact with proper input validation, output encoding, and Content Security Policy (CSP) headers in place.
🎯 Exploit Status
Exploitation requires low privileges and social engineering but is technically straightforward once an attacker can inject scripts.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions above 8207.27.0
Vendor Advisory: https://www.tibco.com/support/advisories/2021/09/tibco-security-advisory-september-14-2021-tibco-webfocus-2021-35493
Restart Required: Yes
Instructions:
1. Download updated versions from TIBCO support portal. 2. Apply patches to all affected components. 3. Restart services. 4. Verify successful update.
🔧 Temporary Workarounds
Implement Content Security Policy
allAdd CSP headers to restrict script execution sources
Add 'Content-Security-Policy' header with appropriate directives to web server configuration
Input Validation and Output Encoding
allImplement server-side validation and proper output encoding for user inputs
Implement input validation filters and output encoding functions in application code
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block XSS payloads
- Restrict user privileges and implement principle of least privilege
🔍 How to Verify
Check if Vulnerable:
Check installed version against affected version range (8207.27.0 and below)Check Version:
Check version through WebFOCUS administration interface or installation logsVerify Fix Applied:
Verify version is above 8207.27.0 and test for XSS vulnerabilities using security scanners📡 Detection & Monitoring
Log Indicators:
- Unusual script tags or JavaScript in user inputs
- Multiple failed XSS attempts in logs
Network Indicators:
- Suspicious script payloads in HTTP requests
- Unexpected external script loads
SIEM Query:
Search for patterns like '<script>', 'javascript:', or encoded XSS payloads in web request logs🔗 References
- https://www.tibco.com/services/support/advisories
- https://www.tibco.com/support/advisories/2021/09/tibco-security-advisory-september-14-2021-tibco-webfocus-2021-35493
- https://www.tibco.com/services/support/advisories
- https://www.tibco.com/support/advisories/2021/09/tibco-security-advisory-september-14-2021-tibco-webfocus-2021-35493
