CVE-2025-14993
📋 TL;DR
This CVE describes a remote stack-based buffer overflow vulnerability in Tenda AC18 routers. Attackers can exploit this by sending specially crafted HTTP requests to the vulnerable SetDlnaCfg endpoint, potentially allowing arbitrary code execution. All users running the affected firmware version are at risk.
💻 Affected Systems
- Tenda AC18
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise leading to persistent backdoor installation, credential theft, network pivoting, and botnet recruitment.
Likely Case
Router takeover enabling traffic interception, DNS manipulation, and lateral movement into connected networks.
If Mitigated
Limited impact if device is behind strict network segmentation with no internet exposure.
🎯 Exploit Status
Public proof-of-concept available; exploitation requires sending crafted HTTP request to vulnerable endpoint.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: Yes
Instructions:
1. Check Tenda website for firmware updates
2. If update available, download and flash via web interface
3. Factory reset after update
4. Reconfigure with secure settings
🔧 Temporary Workarounds
Disable DLNA Service
allDisable the vulnerable DLNA service if not needed
Network Segmentation
allIsolate router management interface from untrusted networks
🧯 If You Can't Patch
- Replace vulnerable device with supported model
- Implement strict network access controls to block traffic to port 80/443 on router
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router web interface; if version is 15.03.05.05, device is vulnerable.Check Version:
Check via router web interface or SSH if enabled: cat /proc/versionVerify Fix Applied:
Verify firmware version has changed from 15.03.05.05 to a newer version.📡 Detection & Monitoring
Log Indicators:
- HTTP POST requests to /goform/SetDlnaCfg with unusual parameters
- Router crash/reboot logs
Network Indicators:
- Unusual HTTP traffic to router management interface from external sources
SIEM Query:
source_ip=external AND dest_ip=router_ip AND http_uri="/goform/SetDlnaCfg" AND http_method=POST🔗 References
- https://github.com/z472421519/BinaryAudit/blob/main/PoC/BOF/Tenda_AC18/SetDlnaCfg/SetDlnaCfg.md
- https://github.com/z472421519/BinaryAudit/blob/main/PoC/BOF/Tenda_AC18/SetDlnaCfg/SetDlnaCfg.md#reproduce
- https://vuldb.com/?ctiid.337687
- https://vuldb.com/?id.337687
- https://vuldb.com/?submit.719084
- https://www.tenda.com.cn/
