CVE-2024-20300
📋 TL;DR
This CVE describes a cross-site scripting (XSS) vulnerability in Cisco Firepower Management Center's web interface that allows authenticated attackers to inject malicious scripts. When exploited, it could enable attackers to execute arbitrary JavaScript in victims' browsers, potentially stealing session cookies or performing unauthorized actions. Only authenticated users with access to the FMC web interface can exploit this vulnerability.
💻 Affected Systems
- Cisco Firepower Management Center (FMC)
📦 What is this software?
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
Secure Firewall Management Center by Cisco
⚠️ Risk & Real-World Impact
Worst Case
An authenticated attacker could steal administrator session cookies, hijack administrative sessions, perform unauthorized configuration changes, or deploy malicious scripts to other users of the FMC interface.
Likely Case
An authenticated attacker with limited privileges could escalate privileges by stealing session cookies from administrators or performing unauthorized actions within their own authenticated context.
If Mitigated
With proper input validation and output encoding implemented, the vulnerability would be neutralized, preventing script injection while maintaining interface functionality.
🎯 Exploit Status
Exploitation requires authenticated access; attacker needs to craft malicious input in specific data fields that lack proper validation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 7.4.1 or 7.2.5.1
Vendor Advisory: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-xss-M446vbEO
Restart Required: Yes
Instructions:
1. Backup current configuration. 2. Download appropriate patch from Cisco Software Center. 3. Apply patch following Cisco upgrade procedures. 4. Reboot system as required. 5. Verify successful upgrade and functionality.
🔧 Temporary Workarounds
Input Validation Enhancement
allImplement additional input validation on affected data fields to sanitize user input before processing.
Content Security Policy
allImplement strict Content Security Policy headers to restrict script execution sources.
🧯 If You Can't Patch
- Restrict access to FMC web interface to trusted networks only using firewall rules
- Implement web application firewall (WAF) rules to detect and block XSS payloads
🔍 How to Verify
Check if Vulnerable:
Check FMC software version via web interface: System > Updates > Version InformationCheck Version:
ssh admin@fmc-host 'show version' or check web interfaceVerify Fix Applied:
Verify version is 7.4.1 or 7.2.5.1 or later, then test affected data fields with XSS payloads to confirm sanitization📡 Detection & Monitoring
Log Indicators:
- Unusual input patterns in web interface logs
- Multiple failed XSS attempts in web server logs
- Suspicious JavaScript payloads in request parameters
Network Indicators:
- HTTP requests containing script tags or JavaScript payloads to FMC interface
- Unusual patterns of authenticated requests to data fields
SIEM Query:
source="fmc_web_logs" AND ("<script>" OR "javascript:" OR "onerror=" OR "onload=")