CVE-2024-25748 Overview
CVE-2024-25748 is a stack-based buffer overflow vulnerability affecting the Tenda AC9 v3.0 router running firmware version v.15.03.06.42_multi. The flaw resides in the fromSetIpMacBind function of the device's web management interface. A remote attacker on an adjacent network can send a crafted request that overflows a stack buffer, leading to arbitrary code execution on the device. The weakness is classified under CWE-121 (Stack-Based Buffer Overflow). Successful exploitation grants attacker-controlled code execution in the router firmware context.
Critical Impact
Adjacent-network attackers can execute arbitrary code on affected Tenda AC9 routers, gaining full control of the device and any traffic passing through it.
Affected Products
- Tenda AC9 v3.0 (hardware)
- Tenda AC9 firmware version v.15.03.06.42_multi
- Tenda AC9 firmware CPE 5.03.06.42_multi
Discovery Timeline
- 2024-02-22 - CVE-2024-25748 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-25748
Vulnerability Analysis
The vulnerability exists in the fromSetIpMacBind handler exposed by the AC9's HTTP-based management interface. This function processes IP-to-MAC binding entries submitted by administrators through the web UI. The handler copies attacker-supplied parameters into a fixed-size stack buffer without validating the input length. When the input exceeds the buffer boundary, adjacent stack memory — including the saved return address — is overwritten.
An attacker on the same network segment as the router can reach the management interface and submit a crafted request containing an oversized field. By carefully sizing the payload, the attacker overwrites the return address and redirects execution flow. Because Tenda consumer routers typically run without address space layout randomization (ASLR) or non-executable stack protections, exploitation is deterministic. Code execution occurs with the privileges of the web server process, which on these devices runs as root.
See the public proof-of-concept writeup for the specific parameter and offset details.
Root Cause
The root cause is missing bounds checking on user-controlled input before it is copied into a stack-allocated buffer inside fromSetIpMacBind. The function trusts that request parameters conform to expected sizes and passes them to unsafe string operations such as strcpy or sprintf. This pattern is the canonical [CWE-121] stack buffer overflow.
Attack Vector
Exploitation requires network adjacency, meaning the attacker must be connected to the same LAN or Wi-Fi segment as the router. Authentication is not required in the exploitation path documented publicly. The attacker sends a single HTTP POST request to the vulnerable endpoint containing an overlong field that overflows the stack buffer and hijacks control flow. No user interaction is required.
The vulnerability mechanism is documented in the public proof-of-concept. No verified exploit code is republished here; refer to the external reference for reproduction details.
Detection Methods for CVE-2024-25748
Indicators of Compromise
- Unexpected outbound connections originating from the router's management IP to unknown hosts.
- HTTP POST requests to the router's /goform/ endpoints containing abnormally long parameter values, especially targeting fromSetIpMacBind.
- Unexplained reboots, crashes, or configuration changes on the AC9 device.
- New or unknown DNS resolvers configured on the router without administrator action.
Detection Strategies
- Inspect HTTP request bodies destined for the router's web interface for parameter lengths exceeding reasonable thresholds (for example, IP or MAC fields longer than 64 bytes).
- Deploy network intrusion detection signatures that match oversized POST payloads to Tenda /goform/setIpMacBind paths.
- Correlate router syslog entries with authentication events to spot anomalous administrative sessions from adjacent hosts.
Monitoring Recommendations
- Segment the router management VLAN and log all traffic reaching the administrative interface.
- Alert on any device on a guest or user VLAN attempting to reach the router management IP on TCP/80 or TCP/443.
- Baseline outbound traffic from the router itself; investigate deviations that could indicate implanted code.
How to Mitigate CVE-2024-25748
Immediate Actions Required
- Restrict access to the router's web management interface to a trusted management VLAN only.
- Disable remote (WAN-side) administration if it is enabled.
- Change default administrator credentials and enforce strong passwords to raise the bar for reaching the vulnerable endpoint.
- Isolate affected AC9 devices from untrusted user segments until a vendor patch is applied.
Patch Information
No vendor advisory or fixed firmware version has been published in the enriched CVE data for CVE-2024-25748. Administrators should monitor the Tenda support portal for updated firmware addressing the fromSetIpMacBind handler and apply it as soon as it becomes available. For high-risk environments, consider replacing the affected AC9 v3.0 hardware with a supported alternative.
Workarounds
- Place the AC9 behind a firewall that filters HTTP traffic to its management interface from untrusted hosts.
- Enforce Wi-Fi client isolation so that connected clients cannot reach the router's LAN-side management IP directly.
- Disable IP-MAC binding features in the web UI where feasible to reduce interaction with the vulnerable code path, understanding that the endpoint may remain reachable.
- Monitor the public PoC reference and vendor channels for updated mitigation guidance.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
