CVE-2025-7416 is a critical stack-based buffer overflow vulnerability identified in the Tenda O3V2 device, specifically version 1.0.0.12(3880). The flaw exists in the httpd component within the fromSysToolTime function of the /goform/setSysTimeInfo endpoint. The vulnerability arises due to improper handling and validation of the 'Time' argument passed to this function, allowing an attacker to overflow the stack buffer. This overflow can corrupt adjacent memory, potentially enabling arbitrary code execution or causing a denial of service. The vulnerability is remotely exploitable without requiring user interaction or prior authentication, as indicated by the CVSS vector (AV:N/AC:L/AT:N/UI:N/PR:L). The presence of a public exploit disclosure increases the risk of exploitation, although no confirmed exploits in the wild have been reported yet. The CVSS 4.0 base score of 8.7 reflects the high severity, with high impact on confidentiality, integrity, and availability, and relatively low attack complexity. The vulnerability affects a specific firmware version of the Tenda O3V2 device, which is typically used as a networking device such as a router or wireless access point. Successful exploitation could allow attackers to gain control over the device, intercept or manipulate network traffic, or pivot into internal networks, posing significant security risks.

For European organizations, the exploitation of CVE-2025-7416 could have severe consequences. Many enterprises and small-to-medium businesses rely on Tenda networking equipment for internet connectivity and internal network segmentation. Compromise of these devices could lead to unauthorized access to sensitive corporate data, interception of communications, disruption of business operations through denial of service, and potential lateral movement within corporate networks. Given the remote exploitability and lack of required user interaction, attackers could target vulnerable devices en masse, potentially impacting critical infrastructure sectors such as finance, healthcare, and manufacturing. Additionally, the integrity of network traffic could be undermined, facilitating espionage or data exfiltration. The public availability of exploits increases the urgency for mitigation to prevent widespread attacks.

To mitigate this vulnerability, European organizations should first identify any Tenda O3V2 devices running firmware version 1.0.0.12(3880) within their networks. Since no official patches are currently linked, organizations should contact Tenda support for firmware updates or advisories. In the interim, network administrators should restrict access to the management interface of affected devices by implementing network segmentation and firewall rules to limit exposure to trusted IP addresses only. Disabling remote management features or changing default management ports can reduce attack surface. Monitoring network traffic for unusual activity targeting the /goform/setSysTimeInfo endpoint is recommended. Employing intrusion detection/prevention systems (IDS/IPS) with signatures for this exploit can help detect and block exploitation attempts. Organizations should also consider replacing vulnerable devices with updated or alternative hardware if patches are unavailable. Finally, maintaining an asset inventory and regularly auditing device firmware versions will aid in timely vulnerability management.