CVE-2025-14286
📋 TL;DR
This vulnerability in Tenda AC9 routers allows remote attackers to access configuration files via the /cgi-bin/DownloadCfg.jpg endpoint, potentially exposing sensitive router settings and credentials. It affects Tenda AC9 routers running firmware version 15.03.05.14_multi. Attackers can exploit this without authentication to gather information for further attacks.
💻 Affected Systems
- Tenda AC9
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Attackers obtain router admin credentials, network configuration details, and potentially gain full control of the router to intercept traffic, modify settings, or pivot to internal networks.
Likely Case
Attackers download router configuration files containing Wi-Fi passwords, admin credentials, and network topology information for reconnaissance or credential reuse attacks.
If Mitigated
With proper network segmentation and firewall rules, impact is limited to information disclosure from the router itself without lateral movement opportunities.
🎯 Exploit Status
Exploit involves simple HTTP GET request to vulnerable endpoint; proof-of-concept code is publicly available on GitHub.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.tenda.com.cn/
Restart Required: No
Instructions:
Check Tenda website for firmware updates. If available, download latest firmware and apply through router admin interface.
🔧 Temporary Workarounds
Block External Access to Router Admin
allConfigure firewall to block WAN access to router admin interface (typically port 80/443)
Disable Remote Management
allTurn off remote management feature in router settings if enabled
🧯 If You Can't Patch
- Replace affected router with updated model or different vendor
- Segment router management to isolated VLAN with strict access controls
🔍 How to Verify
Check if Vulnerable:
Attempt to access http://[router-ip]/cgi-bin/DownloadCfg.jpg from network; if configuration file downloads, system is vulnerable.Check Version:
Check router web interface or use nmap -sV -p80,443 [router-ip] to identify firmware versionVerify Fix Applied:
After firmware update, attempt same access; should return error or deny access.📡 Detection & Monitoring
Log Indicators:
- HTTP GET requests to /cgi-bin/DownloadCfg.jpg
- Unusual configuration file access patterns
Network Indicators:
- External IPs accessing router admin interface
- Multiple failed then successful access to DownloadCfg.jpg
SIEM Query:
source="router_logs" AND uri="/cgi-bin/DownloadCfg.jpg"