CVE-2022-25417
📋 TL;DR
CVE-2022-25417 is a critical stack overflow vulnerability in Tenda AC9 routers that allows remote attackers to execute arbitrary code by sending specially crafted requests to the saveparentcontrolinfo function. This affects users of Tenda AC9 routers running vulnerable firmware versions. Successful exploitation could lead to complete device compromise.
💻 Affected Systems
- Tenda AC9
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote unauthenticated attacker gains full control of the router, enabling traffic interception, credential theft, network pivoting, and persistent backdoor installation.
Likely Case
Attacker executes arbitrary code with root privileges, enabling router takeover, DNS manipulation, and network surveillance.
If Mitigated
With proper network segmentation and access controls, impact limited to isolated IoT network segment.
🎯 Exploit Status
Public proof-of-concept available in GitHub repository. Exploitation requires sending crafted HTTP request to vulnerable endpoint.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: V15.03.2.22_cn or later
Vendor Advisory: https://www.tenda.com.cn/security/
Restart Required: Yes
Instructions:
1. Log into router admin interface 2. Navigate to System Tools > Firmware Upgrade 3. Download latest firmware from Tenda website 4. Upload and install firmware 5. Reboot router
🔧 Temporary Workarounds
Disable Remote Management
allPrevent external access to router management interface
Navigate to Advanced > System Tools > Remote Management and disable
Network Segmentation
allIsolate router management interface to trusted network
Configure firewall rules to restrict access to router IP on ports 80/443
🧯 If You Can't Patch
- Replace vulnerable router with supported model from different vendor
- Implement strict network ACLs to block all traffic to router management interface except from trusted administrative hosts
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router admin interface under System Status > Firmware VersionCheck Version:
curl -s http://router-ip/goform/getStatus | grep versionVerify Fix Applied:
Confirm firmware version is V15.03.2.22_cn or later after patching📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP POST requests to /goform/saveParentControlInfo
- Multiple failed authentication attempts followed by successful exploit
Network Indicators:
- Unusual outbound connections from router to unknown IPs
- DNS queries to suspicious domains from router
SIEM Query:
source="router.log" AND (uri="/goform/saveParentControlInfo" OR method="POST" AND user_agent="Mozilla*" AND size>1000)