CVE-2025-51089: Heap Overflow in Tenda AC8V4 Router
Tenda AC8V4 routers, specifically version V16.03.34.06, are affected by a heap overflow vulnerability that could allow attackers to disrupt the device's functionality. This vulnerability resides within the web interface and is triggered by manipulating the `mac` argument in a request to `/goform/GetParentControlInfo`.
Vulnerability Details
- CVE ID: CVE-2025-51089
- Description: A heap overflow vulnerability exists in Tenda AC8V4 V16.03.34.06 at `/goform/GetParentControlInfo`. Manipulating the `mac` argument leads to a heap-based buffer overflow.
- CVSS Score: 6.5 (Medium)
- CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
- CVSS Explanation: This means an attacker on the network can trigger the vulnerability without needing any credentials or user interaction. The impact is limited to a potential loss of integrity (e.g., changing settings) or availability (e.g., crashing the router).
- Exploit Requirements: Network access to the router's web interface is required. No authentication is needed to trigger the vulnerability.
Affected Products:
- Vendor: Tenda
- Product: AC8V4
- Version: V16.03.34.06
CWE
- CWE ID: CWE-122
- CWE Name: Heap-based Buffer Overflow
- CWE Explanation: A heap-based buffer overflow occurs when data is written beyond the allocated memory on the heap, potentially overwriting adjacent data structures and leading to unexpected program behavior, crashes, or even arbitrary code execution.
Timeline of Events
- 2025-07-24: Vulnerability publicly disclosed.
- 2025-07-24: CVE ID assigned.
Exploitability & Real-World Risk
This vulnerability is relatively easy to exploit, as it requires no authentication and can be triggered with a simple HTTP request. In a real-world scenario, an attacker could potentially exploit this vulnerability to disrupt network services, redirect traffic, or even gain control of the router. Given the prevalence of Tenda routers in home and small business environments, this poses a significant risk.
Recommendations
- Check for Firmware Updates: Visit the Tenda website or use the router's web interface to check for and install any available firmware updates. This is the most effective way to mitigate the vulnerability.
- Disable Remote Management: If you don't need to access your router's settings remotely, disable remote management to reduce the attack surface.
- Monitor Network Traffic: Keep an eye on your network traffic for any unusual activity.
Technical Insight
The vulnerability stems from insufficient bounds checking when processing the `mac` argument in the `/goform/GetParentControlInfo` endpoint. By providing a `mac` value larger than the allocated buffer on the heap, an attacker can overwrite adjacent memory regions. This can lead to a denial of service or potentially allow for code execution, depending on the overwritten data.
Credit to Researcher(s)
This vulnerability was discovered by TL-SN and reported through GitHub.
References
Tags
#CVE-2025-51089 #Tenda #AC8V4 #Router #HeapOverflow #IoT #Security
Summary: A heap overflow vulnerability exists in Tenda AC8V4 routers (V16.03.34.06) allowing remote attackers to cause a denial of service or potentially gain limited control via crafted requests to the /goform/GetParentControlInfo endpoint. Firmware updates are strongly recommended.
CVE ID: CVE-2025-51089
Risk Analysis: Successful exploitation could lead to denial of service (router crash), potentially allowing an attacker to disrupt network connectivity or, in a more severe scenario, gain limited control over the router.
Recommendation: Update to the latest firmware version provided by Tenda. If an update is not available, consider disabling remote management of the router.
Timeline
- 2025-07-24: Vulnerability published and CVE ID assigned.