CVE-2024-56316
📋 TL;DR
This vulnerability allows remote unauthenticated attackers to send crafted TR069 requests to AXESS ACS servers, causing permanent Denial of Service that persists even after rebooting. It affects all AXESS ACS versions through 5.2.0 that expose the TR069 API on TCP ports 9675 or 7547. The vulnerability stems from unsanitized user input in the TR069 API implementation.
💻 Affected Systems
- AXESS Auto Configuration Server (ACS)
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Complete and permanent service disruption of the Auto Configuration Server, preventing device provisioning and management across the entire network, requiring complete system restoration from backups.
Likely Case
Persistent DoS affecting the ACS service, disrupting automated device configuration and management for connected customer premises equipment (CPE).
If Mitigated
No impact if the TR069 API is not exposed to untrusted networks or if proper input validation is implemented.
🎯 Exploit Status
Exploitation requires sending crafted TR069 requests but does not require authentication or special privileges. The vulnerability is in the TR069 protocol implementation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version after 5.2.0 (check vendor for specific fixed version)
Vendor Advisory: https://www.y-security.de/news-en/axess-auto-configuration-server-denial-of-service-cve-2024-56316/
Restart Required: No
Instructions:
1. Contact AXESS support for the patched version. 2. Backup current configuration. 3. Apply the vendor-provided patch or upgrade to fixed version. 4. Verify service functionality post-update.
🔧 Temporary Workarounds
Network Access Control
allRestrict access to TR069 API ports (9675, 7547) to only trusted management networks using firewall rules.
Input Validation Enhancement
allImplement additional input validation and sanitization for TR069 requests at network perimeter or load balancer level.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate ACS servers from untrusted networks
- Deploy intrusion prevention systems (IPS) with rules to detect and block malformed TR069 requests
🔍 How to Verify
Check if Vulnerable:
Check if AXESS ACS version is 5.2.0 or earlier and TR069 API is listening on ports 9675 or 7547 using netstat or similar tools.Check Version:
Check ACS web interface or configuration files for version information, or consult vendor documentation.Verify Fix Applied:
Verify version is above 5.2.0 and test with legitimate TR069 requests to ensure service remains available.📡 Detection & Monitoring
Log Indicators:
- Unusual TR069 request patterns
- ACS service crashes or restarts
- High volume of malformed requests to ports 9675/7547
Network Indicators:
- Abnormal TR069 traffic patterns
- Crafted requests to ACS ports
- DoS conditions affecting ACS service
SIEM Query:
source_port:9675 OR source_port:7547 AND (protocol:TR069 OR service:acs) AND (event_type:attack OR severity:high)