CVE-2025-57058 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 in the formSetDebugCfg function, specifically triggered via the pEnable, pLevel, and pModule parameters. Stack overflows occur when a program writes more data to a buffer located on the stack than it can hold, potentially overwriting adjacent memory and causing unpredictable behavior. In this case, the overflow can be exploited by an attacker sending a specially crafted request to the vulnerable router, leading to a Denial of Service (DoS) condition. The CVSS 3.1 base score of 7.5 reflects that the vulnerability can be exploited remotely (AV:N), with low attack complexity (AC:L), no privileges required (PR:N), and no user interaction needed (UI:N). The impact is limited to availability (A:H), with no confidentiality or integrity impact. The vulnerability is categorized under CWE-121 (Stack-based Buffer Overflow). No known exploits are reported in the wild yet, and no patches have been linked or published at this time. The vulnerability was reserved on August 17, 2025, and published on September 9, 2025. The lack of authentication or user interaction requirements makes this vulnerability particularly concerning for exposed devices. Given that Tenda G3 routers are consumer-grade networking devices, exploitation could disrupt network connectivity for affected users or organizations by crashing the device or causing it to reboot. This could lead to temporary loss of internet access or internal network disruption.

For European organizations, the primary impact of this vulnerability is the potential disruption of network services due to Denial of Service attacks on Tenda G3 routers. Organizations relying on these routers for internet connectivity or internal network routing could experience outages, impacting business operations, communications, and access to cloud services. While the vulnerability does not directly compromise confidentiality or data integrity, the availability impact could be significant for small and medium enterprises or branch offices using these devices without robust network redundancy. Critical infrastructure or organizations with remote sites using Tenda G3 routers could face operational interruptions. Additionally, if attackers leverage this vulnerability as part of a larger attack chain, it could serve as a foothold or distraction while other attacks are conducted. The lack of known exploits currently reduces immediate risk, but the ease of exploitation and no requirement for authentication suggest a high potential for future exploitation. European organizations with exposed or poorly secured Tenda G3 devices are at risk of targeted or opportunistic DoS attacks.

1. Immediate mitigation should include identifying all Tenda G3 routers running firmware version 3.0br_V15.11.0.17 within the network. 2. Restrict remote management access to these devices by disabling WAN-side management interfaces or limiting access via firewall rules to trusted IP addresses only. 3. Monitor network traffic for unusual or malformed requests targeting the formSetDebugCfg function or related parameters. 4. Implement network segmentation to isolate vulnerable devices from critical infrastructure and sensitive data. 5. Regularly check for firmware updates or security advisories from Tenda and apply patches promptly once available. 6. If patching is not immediately possible, consider replacing vulnerable devices with models from vendors with active security support. 7. Employ intrusion detection/prevention systems (IDS/IPS) capable of detecting exploitation attempts targeting stack overflow vulnerabilities in router management interfaces. 8. Educate IT staff on the risks of exposed management interfaces and enforce strong network device hardening policies. 9. Maintain up-to-date asset inventories to quickly identify and remediate vulnerable devices in the future.