CVE-2025-25453 Overview
CVE-2025-25453 is a buffer overflow vulnerability in the Tenda AC10 wireless router, firmware version V4.0si_V16.03.10.20. The flaw resides in the AdvSetMacMtuWan handler and is triggered through the serviceName2 parameter. An attacker who can reach the router's management interface and supply a crafted request can corrupt stack memory, potentially impacting confidentiality, integrity, and availability of the device. The weakness is classified as [CWE-120] (Buffer Copy without Checking Size of Input).
Critical Impact
Successful exploitation can corrupt memory in a widely deployed consumer router, leading to denial of service or possible code execution on the device.
Affected Products
- Tenda AC10 hardware revision 4.0
- Tenda AC10 firmware V4.0si_V16.03.10.20
- Deployments exposing the router web management interface to untrusted networks
Discovery Timeline
- 2025-04-15 - CVE-2025-25453 published to the National Vulnerability Database (NVD)
- 2026-06-17 - Last updated in NVD
Technical Details for CVE-2025-25453
Vulnerability Analysis
The vulnerability exists in the AdvSetMacMtuWan function used by the Tenda AC10 web management service to configure WAN MAC address and MTU settings. The handler accepts a serviceName2 parameter from HTTP requests and copies the value into a fixed-size stack buffer without validating the input length. Supplying an oversized value overflows the buffer and corrupts adjacent stack data, including saved registers and return addresses on the MIPS-based device.
Exploitation requires network reach to the management interface, authenticated or session-level access, and user interaction, reflecting the elevated attack complexity. Proof-of-concept material is published in a GitHub Gist PoC Script and the companion GitHub Repository Tenda Exploit.
Root Cause
The root cause is missing bounds checking on the serviceName2 request parameter before it is copied into a stack-allocated buffer inside the AdvSetMacMtuWan routine. The firmware trusts attacker-controlled input length and performs an unsafe string copy, matching the [CWE-120] classification.
Attack Vector
An attacker submits a crafted HTTP POST request to the router's /goform/AdvSetMacMtuWan endpoint with a serviceName2 value that exceeds the destination buffer size. The oversized value overwrites the stack frame, enabling denial of service and, with precise payload construction on the MIPS architecture, the possibility of control-flow hijack.
No verified code example is available. See the referenced proof-of-concept repository for technical details.
Detection Methods for CVE-2025-25453
Indicators of Compromise
- HTTP POST requests to /goform/AdvSetMacMtuWan containing abnormally long serviceName2 values.
- Repeated router crashes, reboots, or management interface unresponsiveness following administrative requests.
- Unexpected configuration changes to WAN MAC or MTU settings on affected AC10 devices.
Detection Strategies
- Inspect router access logs and upstream network sensors for requests to AdvSetMacMtuWan with parameter lengths exceeding typical service name sizes.
- Deploy IDS/IPS signatures that flag oversized serviceName2 values in HTTP bodies targeting Tenda web management paths.
- Correlate crash-and-reboot cycles on edge routers with inbound administrative traffic from untrusted sources.
Monitoring Recommendations
- Monitor WAN-side exposure of the router management interface and alert on any external attempts to reach /goform/ endpoints.
- Track LAN clients that generate repeated administrative POST requests to the router, which may indicate internal exploitation attempts.
- Capture SNMP or syslog device-health telemetry to detect abnormal reboot patterns.
How to Mitigate CVE-2025-25453
Immediate Actions Required
- Restrict access to the Tenda AC10 web management interface to trusted internal hosts only and disable WAN-side administration.
- Change default and shared administrative credentials to reduce the risk of authenticated exploitation.
- Audit deployed AC10 devices and identify units running firmware V4.0si_V16.03.10.20.
Patch Information
No vendor advisory or fixed firmware release is listed in the CVE record at the time of publication. Monitor the Tenda support site for an updated firmware image addressing the AdvSetMacMtuWan handler and apply it as soon as it becomes available.
Workarounds
- Place the router behind a segmented management VLAN and block HTTP/HTTPS access to it from untrusted networks.
- Disable remote management features until a patched firmware version is released.
- Replace end-of-support AC10 units with actively maintained hardware if no vendor fix is published.
# Example: block external access to the Tenda web management interface
# Adjust the WAN interface name and router IP for your environment
iptables -A INPUT -i eth0 -p tcp --dport 80 -d 192.168.0.1 -j DROP
iptables -A INPUT -i eth0 -p tcp --dport 443 -d 192.168.0.1 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
