CVE-2024-20461
📋 TL;DR
This vulnerability in Cisco ATA 190 Series Analog Telephone Adapters allows authenticated local attackers with high privileges to execute arbitrary commands as root due to improper CLI input sanitization. It affects organizations using these devices for analog telephone connectivity. Attackers could gain complete control over the device's underlying operating system.
💻 Affected Systems
- Cisco ATA 190 Series Analog Telephone Adapter
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attackers to read/write all files, install persistent backdoors, pivot to other network systems, and intercept/modify all telephone traffic.
Likely Case
Privileged attackers gaining root access to modify device configuration, intercept calls, or use the device as a foothold for lateral movement.
If Mitigated
Limited impact if proper access controls prevent unauthorized local access and CLI usage is restricted.
🎯 Exploit Status
Exploitation requires sending malicious characters to the CLI interface by an authenticated high-privilege user.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Refer to Cisco Security Advisory for specific fixed versions
Vendor Advisory: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ata19x-multi-RDTEqRsy
Restart Required: Yes
Instructions:
1. Review Cisco Security Advisory for fixed firmware versions. 2. Download appropriate firmware from Cisco. 3. Backup current configuration. 4. Upload and install new firmware via web interface or CLI. 5. Verify installation and restore configuration if needed.
🔧 Temporary Workarounds
Restrict CLI Access
allLimit CLI access to only authorized administrators and implement strict access controls.
Implement Network Segmentation
allIsolate ATA devices on separate VLANs to limit lateral movement potential.
🧯 If You Can't Patch
- Implement strict access controls to prevent unauthorized local access to devices
- Monitor CLI access logs for suspicious activity and implement alerting
🔍 How to Verify
Check if Vulnerable:
Check firmware version via web interface or CLI and compare against fixed versions in Cisco advisory.Check Version:
show version (via CLI) or check web interface System Information pageVerify Fix Applied:
Verify firmware version matches or exceeds fixed version listed in Cisco Security Advisory.📡 Detection & Monitoring
Log Indicators:
- Unusual CLI command patterns
- Multiple failed authentication attempts followed by successful access
- Commands containing special characters or shell metacharacters
Network Indicators:
- Unusual network traffic from ATA devices
- Connections to unexpected external IPs
SIEM Query:
source="cisco_ata" AND (event_type="cli_command" AND command="*[;|&`]*")