CVE-2025-57060 is a stack overflow vulnerability identified in the Tenda G3 router firmware version 3.0br_V15.11.0.17. The flaw exists in the dns_forward_rule_store function, specifically within the handling of the 'rules' parameter. A stack overflow occurs when the function processes a crafted request containing maliciously crafted data in this parameter, leading to memory corruption. This vulnerability can be exploited by an attacker to cause a Denial of Service (DoS) condition, effectively crashing or rebooting the device, thereby disrupting network connectivity. The vulnerability does not appear to require authentication or user interaction, as it can be triggered remotely via a crafted request. No known exploits are currently reported in the wild, and no CVSS score has been assigned yet. The lack of a patch or mitigation details suggests that the vulnerability is newly disclosed and may require urgent attention from affected users and vendors. The impact is primarily on availability, as the stack overflow leads to service disruption rather than direct code execution or data leakage. However, stack overflows can sometimes be leveraged for more severe attacks if combined with other vulnerabilities, though no such indications are present here.

For European organizations, the primary impact of CVE-2025-57060 is the potential disruption of network services relying on Tenda G3 routers. These routers are often used in small to medium business environments and home offices, so a successful DoS attack could interrupt internet access, intranet communications, and critical business operations dependent on network availability. In sectors such as finance, healthcare, and manufacturing, even short-term network outages can lead to operational delays, loss of productivity, and potential regulatory compliance issues. Additionally, if attackers use this vulnerability as part of a broader attack campaign, it could serve as a vector to degrade organizational resilience. While the vulnerability does not directly compromise confidentiality or integrity, the loss of availability can have cascading effects on business continuity and incident response capabilities. European organizations with remote or distributed workforces may be particularly vulnerable if these routers are deployed in home office environments without centralized management or monitoring.

Given the absence of an official patch or vendor advisory, European organizations should take proactive steps to mitigate the risk. First, identify and inventory all Tenda G3 routers running firmware version 3.0br_V15.11.0.17 within the network and connected remote environments. Where possible, isolate these devices from untrusted networks and restrict access to management interfaces using firewall rules or network segmentation. Implement strict ingress filtering to block malformed or suspicious DNS forwarding requests that could exploit the vulnerable parameter. Monitor network traffic for anomalous patterns targeting DNS forwarding functions. Engage with Tenda support channels to obtain firmware updates or patches addressing this vulnerability and plan for timely deployment once available. As a temporary measure, consider disabling DNS forwarding features if not essential to operations. Additionally, educate IT staff and users about the risks and signs of DoS attacks to enable rapid detection and response. Finally, maintain up-to-date backups and incident response plans to minimize operational impact in case of exploitation.