CVE-2024-20273
📋 TL;DR
An unauthenticated cross-site scripting (XSS) vulnerability in Cisco Firepower Management Center's web interface allows remote attackers to inject malicious scripts. This could lead to session hijacking, data theft, or unauthorized actions when administrators view compromised pages. All organizations using vulnerable FMC versions are affected.
💻 Affected Systems
- Cisco Firepower Management Center
📦 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
⚠️ Risk & Real-World Impact
Worst Case
Attacker gains administrative access to FMC, modifies firewall rules, exfiltrates sensitive network data, or deploys malware across managed devices.
Likely Case
Attacker steals administrator session cookies, gains unauthorized access to the management interface, and performs limited configuration changes.
If Mitigated
With proper network segmentation and access controls, impact is limited to the management interface without compromising core network security functions.
🎯 Exploit Status
Exploitation requires tricking authenticated users into visiting malicious links or interacting with crafted input.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 7.4.1.2 or 7.6.0.1
Vendor Advisory: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-xss-M446vbEO
Restart Required: Yes
Instructions:
1. Backup FMC configuration. 2. Download appropriate patch from Cisco Software Center. 3. Apply patch via FMC web interface or CLI. 4. Reboot system after patch installation.
🔧 Temporary Workarounds
Network Access Restriction
allRestrict access to FMC web interface to trusted IP addresses only
Browser Security Controls
allImplement Content Security Policy headers and disable JavaScript for untrusted sources
🧯 If You Can't Patch
- Implement strict network segmentation to isolate FMC from untrusted networks
- Require multi-factor authentication for all administrative access
🔍 How to Verify
Check if Vulnerable:
Check FMC version via web interface: System > Updates > Version InformationCheck Version:
show versionVerify Fix Applied:
Verify version is 7.4.1.2 or 7.6.0.1 or later after patching📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP requests with script tags to FMC interface
- Multiple failed login attempts followed by successful access from new IP
Network Indicators:
- HTTP traffic to FMC containing suspicious JavaScript payloads
- Outbound connections from FMC to unexpected external IPs
SIEM Query:
source="fmc.log" AND (http_uri="*<script*" OR http_uri="*javascript:*")