CVE-2025-8017 Overview
CVE-2025-8017 is a stack-based buffer overflow in the Tenda AC7 wireless router running firmware version 15.03.06.44. The flaw resides in the formSetMacFilterCfg function handling requests to /goform/setMacFilterCfg within the embedded httpd web service. Attackers can manipulate the deviceList argument to corrupt the stack and influence program execution. The vulnerability is remotely reachable over the network and the technical details have been publicly disclosed. The weakness is tracked under [CWE-119] for improper restriction of operations within the bounds of a memory buffer.
Critical Impact
Remote attackers with low privileges can trigger a stack overflow in the router's HTTP daemon, enabling denial of service and potential arbitrary code execution on the device.
Affected Products
- Tenda AC7 hardware revision 1.0
- Tenda AC7 firmware 15.03.06.44
- Embedded httpd component handling /goform/setMacFilterCfg
Discovery Timeline
- 2025-07-22 - CVE-2025-8017 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-8017
Vulnerability Analysis
The Tenda AC7 router exposes a web management interface served by an embedded httpd binary. One of the request handlers, formSetMacFilterCfg, processes MAC address filter configuration submitted to the endpoint /goform/setMacFilterCfg. The handler reads the user-supplied deviceList parameter and copies it into a fixed-size stack buffer without validating the input length. Sending an oversized deviceList value overflows that buffer and corrupts adjacent stack data, including the saved return address.
Because the request travels over the network and requires only low-privileged access to the management interface, an attacker on the local network — or any network path that reaches the management UI — can trigger the condition reliably. Public disclosure of the issue increases the likelihood of opportunistic exploitation against exposed devices. The EPSS model places this CVE in a higher exploitation-likelihood band than most published vulnerabilities.
Root Cause
The root cause is missing bounds checking on attacker-controlled input before a copy into a fixed-size stack buffer. The parse_macfilter_rule routine invoked by formSetMacFilterCfg trusts the length of deviceList and uses an unsafe string copy, satisfying the conditions described in [CWE-119].
Attack Vector
An authenticated attacker sends a crafted HTTP POST request to /goform/setMacFilterCfg with an overlong deviceList value. The malformed parameter overruns the destination buffer inside the httpd process, producing a crash or — with a tailored payload aligned to the MIPS-based stack layout — control of execution flow on the device. No verified exploit code example is available; refer to the GitHub PoC writeup and VulDB entry #317220 for the disclosed technical details.
Detection Methods for CVE-2025-8017
Indicators of Compromise
- HTTP POST requests to /goform/setMacFilterCfg containing abnormally long deviceList parameter values.
- Unexpected restarts, crashes, or watchdog reboots of the Tenda AC7 httpd service.
- Outbound connections from the router to unfamiliar hosts following access to the management interface.
Detection Strategies
- Inspect web traffic destined for the router's management interface and alert on deviceList parameter lengths beyond expected MAC list sizes.
- Monitor router system logs for httpd segmentation faults or repeated process restarts.
- Correlate authentication events on the router with subsequent malformed /goform/ requests to identify post-login exploitation attempts.
Monitoring Recommendations
- Forward router syslog output to a centralized log platform and alert on httpd crash signatures.
- Track exposure of the AC7 management interface to untrusted networks using periodic external scans.
- Review network flow data for anomalous traffic originating from the router after configuration changes.
How to Mitigate CVE-2025-8017
Immediate Actions Required
- Restrict access to the router management interface to trusted administrative hosts and VLANs only.
- Disable remote (WAN-side) administration on the AC7 if it is currently enabled.
- Change the default and any weak administrative credentials to reduce the chance of low-privileged abuse.
- Audit existing MAC filter configurations and management session logs for signs of tampering.
Patch Information
No vendor advisory or fixed firmware version is referenced in the published CVE data. Customers should monitor the Tenda official website for an updated firmware release addressing formSetMacFilterCfg and apply it as soon as it becomes available.
Workarounds
- Place the AC7 management interface behind an isolated management VLAN unreachable from guest and IoT segments.
- Block inbound HTTP/HTTPS access to the router's LAN IP from any untrusted subnet using upstream firewall rules.
- Replace end-of-support consumer routers with hardware that receives active security maintenance if a patch is not released.
# Example: restrict access to the AC7 management UI from a Linux gateway
# Replace 192.0.2.10 with the router's LAN IP and 10.10.0.0/24 with the admin subnet
iptables -I FORWARD -p tcp -d 192.0.2.10 --dport 80 -s 10.10.0.0/24 -j ACCEPT
iptables -I FORWARD -p tcp -d 192.0.2.10 --dport 80 -j DROP
iptables -I FORWARD -p tcp -d 192.0.2.10 --dport 443 -s 10.10.0.0/24 -j ACCEPT
iptables -I FORWARD -p tcp -d 192.0.2.10 --dport 443 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
