CVE-2026-3768 is a stack-based buffer overflow vulnerability identified in the Tenda F453 router firmware version 1.0.0.3. The vulnerability resides in the formWrlExtraSet function, specifically in the /goform/WrlExtraSet endpoint, where the GO argument is improperly handled, allowing an attacker to overflow the stack. This type of vulnerability can lead to arbitrary code execution, denial of service, or complete device takeover. The flaw can be exploited remotely over the network without requiring authentication or user interaction, making it highly dangerous. The CVSS 4.0 vector indicates network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:L), no user interaction (UI:N), and high impact on confidentiality, integrity, and availability (VC:H, VI:H, VA:H). Although no known exploits are currently active in the wild, the public disclosure of exploit code increases the likelihood of exploitation attempts. The vulnerability affects only firmware version 1.0.0.3 of the Tenda F453 router, a device commonly used in home and small office environments. The absence of an official patch link suggests that users must rely on vendor updates or implement workarounds to mitigate risk. Given the critical nature of the flaw and the widespread use of Tenda devices, this vulnerability poses a significant threat to network security.

The potential impact of CVE-2026-3768 is severe for organizations using the Tenda F453 router version 1.0.0.3. Successful exploitation can lead to remote code execution, allowing attackers to gain full control over the affected device. This compromises the confidentiality, integrity, and availability of network traffic passing through the router. Attackers could intercept sensitive data, manipulate network configurations, or launch further attacks within the internal network. The vulnerability's remote exploitability without authentication or user interaction increases the attack surface, making it attractive for automated attacks and wormable malware. Small businesses and home users relying on these routers may experience service disruption or data breaches. Larger organizations using these devices in branch offices or less-secured network segments could face lateral movement risks. The public availability of exploit code further elevates the threat level, potentially leading to widespread exploitation if not mitigated promptly.

1. Immediately check for firmware updates from Tenda addressing this vulnerability and apply them as soon as they become available. 2. If no patch is available, disable remote management interfaces on the Tenda F453 router to prevent external access to the vulnerable endpoint. 3. Implement network segmentation to isolate the router from critical internal systems, limiting the impact of a potential compromise. 4. Employ firewall rules to restrict access to the /goform/WrlExtraSet endpoint, allowing only trusted internal IP addresses if remote access is necessary. 5. Monitor network traffic and device logs for unusual activity targeting the vulnerable function or unexpected requests to /goform/WrlExtraSet. 6. Consider replacing affected devices with models from vendors with a stronger security track record if patching is delayed. 7. Educate users and administrators about the risks of this vulnerability and the importance of timely updates and secure configuration. 8. Use intrusion detection/prevention systems (IDS/IPS) to detect and block exploit attempts targeting this vulnerability.