CVE-2025-57061 is a vulnerability identified in the Tenda G3 router firmware version 3.0br_V15.11.0.17. The flaw arises from multiple stack overflow conditions within the formIPMacBindModify function, which processes parameters such as ruleId, ip, mac, v6, and remark. Stack overflow vulnerabilities occur when a program writes more data to a buffer located on the stack than it can hold, potentially overwriting adjacent memory. In this case, the vulnerability can be triggered by sending a specially crafted request containing maliciously crafted values for the aforementioned parameters. Exploiting this flaw allows an attacker to cause a Denial of Service (DoS) condition, effectively crashing or rebooting the device, thereby disrupting network connectivity and availability. The vulnerability does not appear to require authentication or user interaction, increasing its risk profile. No known exploits are currently reported in the wild, and no patches or fixes have been published at the time of this analysis. The absence of a CVSS score suggests that the vulnerability is newly disclosed and has not yet undergone formal severity assessment. However, the technical nature of the flaw—stack overflow leading to DoS—indicates a significant impact on device availability. The affected device, Tenda G3, is a consumer-grade router commonly used in home and small office environments, which may also be deployed in some enterprise edge scenarios. The vulnerability's exploitation vector is network-based, meaning attackers can potentially trigger the DoS remotely without prior access to the device.

For European organizations, the primary impact of CVE-2025-57061 is the potential disruption of network availability due to the forced reboot or crash of Tenda G3 routers. This can lead to loss of internet connectivity, interruption of business operations, and potential cascading effects on dependent services such as VoIP, VPNs, and cloud access. Small and medium enterprises (SMEs) and home offices relying on Tenda G3 devices are particularly vulnerable, as they may lack redundant network infrastructure or rapid incident response capabilities. Additionally, critical sectors such as healthcare, education, and public administration that utilize these routers could face operational downtime. Although the vulnerability does not directly compromise confidentiality or integrity, the denial of service can be leveraged as part of a larger attack chain, for example, as a distraction or to facilitate lateral movement. The lack of known exploits in the wild currently limits immediate risk, but the ease of triggering the vulnerability without authentication raises concerns about potential future exploitation. The absence of patches also means organizations must rely on mitigation strategies until an official fix is released.

Given the lack of an official patch, European organizations should implement several practical mitigations. First, identify and inventory all Tenda G3 routers within their networks to assess exposure. Network segmentation should be employed to isolate vulnerable devices from critical infrastructure and sensitive data. Access to router management interfaces should be restricted using firewall rules and network access control lists (ACLs), limiting exposure to trusted IP addresses only. Monitoring network traffic for unusual or malformed requests targeting the formIPMacBindModify function parameters can help detect attempted exploitation. Organizations should also consider disabling remote management features on these routers if not strictly necessary. Where possible, replace vulnerable Tenda G3 devices with alternative hardware that has received recent security updates. Additionally, maintain regular backups of router configurations to enable rapid recovery in case of device failure. Finally, stay informed on vendor advisories for forthcoming patches and apply them promptly once available.