CVE-2025-57061 is a high-severity vulnerability affecting the Tenda G3 router firmware version 3.0br_V15.11.0.17. The vulnerability arises from multiple stack overflow conditions within the formIPMacBindModify function, which processes parameters such as ruleId, ip, mac, v6, and remark. Stack overflows occur when input data exceeds the allocated buffer size on the call stack, leading to memory corruption. In this case, an attacker can craft malicious requests targeting these parameters to trigger the overflow. The consequence of this vulnerability is a Denial of Service (DoS) condition, where the router may crash or become unresponsive, disrupting network connectivity. The CVSS 3.1 base score is 7.5, indicating a high severity level, with an attack vector of network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), unchanged scope (S:U), no impact on confidentiality or integrity (C:N/I:N), but high impact on availability (A:H). No known exploits are reported in the wild yet, and no patches have been linked at the time of publication. The vulnerability is categorized under CWE-121, which corresponds to stack-based buffer overflows, a common and dangerous class of memory corruption bugs. The lack of authentication and user interaction requirements means that any attacker with network access to the vulnerable device can exploit this flaw remotely, making it a significant risk for exposed devices.

For European organizations, the impact of this vulnerability can be substantial, especially for those relying on Tenda G3 routers in their network infrastructure. The primary impact is the potential for Denial of Service, which can disrupt business operations by causing network outages or degraded performance. This is particularly critical for organizations that depend on continuous internet connectivity or internal network availability, such as financial institutions, healthcare providers, and critical infrastructure operators. Although the vulnerability does not allow data theft or modification, the loss of availability can indirectly affect confidentiality and integrity by interrupting security monitoring, patch management, or incident response capabilities. Additionally, the ease of exploitation without authentication or user interaction increases the risk of automated attacks or worm-like propagation within networks. European organizations with remote or branch offices using these routers may face increased exposure if devices are accessible from the internet or poorly segmented internal networks. The absence of known exploits currently provides a window for proactive mitigation before widespread attacks occur.

Given the absence of an official patch, European organizations should implement several targeted mitigation strategies: 1) Immediately audit network infrastructure to identify any Tenda G3 routers running the vulnerable firmware version. 2) Restrict network access to the management interfaces of these routers by implementing strict firewall rules, allowing only trusted IP addresses or VPN connections. 3) Disable or limit remote management features to reduce exposure to external attackers. 4) Employ network segmentation to isolate vulnerable devices from critical systems and sensitive data. 5) Monitor network traffic for unusual or malformed requests targeting the formIPMacBindModify function parameters, using intrusion detection or prevention systems with custom signatures if possible. 6) Engage with Tenda support channels to obtain firmware updates or official patches as soon as they become available and plan for timely deployment. 7) Consider temporary replacement or upgrade of vulnerable devices in high-risk environments. 8) Educate IT staff about the vulnerability and ensure incident response plans include steps for handling potential DoS events related to this issue.