CVE-2025-8060: Tenda AC23 Remote Stack Overflow Vulnerability

On July 23, 2025, a critical remote stack overflow vulnerability, tracked as CVE-2025-8060, was disclosed in the Tenda AC23 wireless router, potentially enabling denial-of-service (DoS) attacks or arbitrary code execution by unauthenticated attackers. Shared via vulnerability feeds like @VulmonFeeds on X, this flaw affects the device's HTTP request handling, highlighting ongoing security challenges in consumer networking hardware. With no CVSS score assigned yet by the National Vulnerability Database (NVD), but classified as critical by VulDB, users are urged to patch immediately or isolate affected devices to mitigate risks. Below, we break down the vulnerability, its mechanics, potential impacts, and protective measures.

The Vulnerability: Stack-Based Buffer Overflow in setMacFilterCfg

CVE-2025-8060 stems from improper input validation in the setMacFilterCfg function within the /bin/httpd binary of Tenda AC23 firmware version 16.03.07.52_cn. A remote attacker can exploit this by sending a crafted HTTP request with an excessively long 'list' parameter, triggering a stack-based buffer overflow. This flaw allows overwriting of memory on the stack, which could crash the device or, in advanced scenarios, lead to arbitrary code execution if combined with other exploits.The vulnerability was assigned by VulDB as the CVE Numbering Authority (CNA) and appears in feeds like NVD, though detailed assessments are pending. Tenda AC23 routers, popular for home and small business use, run on affected firmware versions, making them prime targets for opportunistic attacks. No proof-of-concept exploits are publicly available on platforms like Vulmon as of disclosure, but the simplicity of the overflow suggests rapid weaponization is possible.

Attack Vectors and Impacts

The primary attack vector is unauthenticated remote access via HTTP, exploiting the router's web management interface exposed to the internet or local network. Attackers can craft malicious requests to the MAC filter configuration endpoint, overflowing the stack without needing credentials. This could be automated in drive-by attacks or targeted scans for vulnerable Tenda devices.Potential impacts include:

• Denial of Service (DoS): Crashing the httpd process or the entire router, disrupting network connectivity for users.
• Arbitrary Code Execution: If the overflow is chained with return-oriented programming (ROP) or other techniques, attackers could gain control of the device, leading to malware implantation, data interception, or botnet recruitment.
• Broader Network Compromise: Compromised routers could serve as pivots for attacking connected devices, especially in home or SMB environments.

Similar stack overflows have been exploited in past Tenda vulnerabilities, such as CVE-2025-29135, indicating a pattern in the vendor's firmware security.

Why Patch ASAP?

As a newly disclosed zero-day (with no prior patches available at time of publication), CVE-2025-8060 carries high exploitation potential, especially given Tenda's history of vulnerabilities and the ease of remote access. Delaying updates could expose devices to automated scans and attacks, particularly since the flaw affects a widely deployed model. Tenda has not yet released a patch, but users should monitor the official website for firmware updates. In the interim, isolating devices or disabling remote management is critical to prevent immediate threats.

Tips for Router Security Hygiene

To protect against CVE-2025-8060 and similar flaws:

• Update Firmware Promptly: Check Tenda's support site for the latest AC23 firmware and apply it immediately once available.
• Disable Remote Management: Avoid exposing the router's web interface to the internet; use local access only.
• Isolate Devices: Place routers behind firewalls or use VLANs to segment networks.
• Monitor for Exploits: Regularly check resources like Vulmon, Exploit-DB, or NVD for proof-of-concepts or active exploits.
• Use Strong Credentials: Change default admin passwords and enable WPA3 encryption for Wi-Fi.
• Network Monitoring: Deploy intrusion detection systems (IDS) to watch for anomalous HTTP traffic targeting the router.

By staying proactive, users can reduce the attack surface. For the latest on CVE-2025-8060, monitor NVD, VulDB, or Tenda's advisories. If your device is affected, consider upgrading to a more secure model until a fix is released.