CVE-2025-9299 is a high-severity stack-based buffer overflow vulnerability affecting the Tenda M3 router, specifically version 1.0.0.12. The flaw exists in the function formGetMasterPassengerAnalyseData within the /goform/getMasterPassengerAnalyseData endpoint. The vulnerability is triggered by manipulating the 'Time' argument, which leads to a stack-based buffer overflow condition. This type of vulnerability allows an attacker to overwrite parts of the stack memory, potentially enabling arbitrary code execution, denial of service, or system compromise. The attack vector is remote network access without requiring user interaction or elevated privileges, making exploitation relatively straightforward. The CVSS 4.0 score is 8.7 (high), reflecting the vulnerability's ease of exploitation (network attack vector, no privileges or user interaction needed) and its impact on confidentiality, integrity, and availability, all rated high. Although no known exploits are currently observed in the wild, the public disclosure of the exploit code increases the risk of imminent attacks. The absence of patches or mitigation links indicates that affected users must rely on other defensive measures until an official fix is released.

For European organizations, the impact of this vulnerability can be significant, especially for enterprises and service providers using Tenda M3 routers in their network infrastructure. Successful exploitation could lead to full compromise of the router, allowing attackers to intercept, modify, or disrupt network traffic, potentially leading to data breaches, espionage, or network outages. This is particularly critical for small and medium-sized businesses or branch offices that rely on consumer-grade routers like the Tenda M3 without advanced security controls. The compromise of network perimeter devices could also serve as a foothold for lateral movement into internal networks, increasing the risk of broader organizational impact. Given the remote attack vector and lack of required authentication, attackers can scan for vulnerable devices across Europe and launch automated attacks, amplifying the threat to critical infrastructure and sensitive data within the region.

1. Immediate network segmentation: Isolate Tenda M3 devices from critical network segments to limit potential lateral movement if compromised. 2. Disable or restrict access to the /goform/getMasterPassengerAnalyseData endpoint if possible, using firewall rules or router access control lists. 3. Monitor network traffic for unusual requests targeting the vulnerable endpoint or abnormal behavior indicative of exploitation attempts. 4. Employ intrusion detection/prevention systems (IDS/IPS) with updated signatures to detect exploitation attempts against this vulnerability. 5. Regularly audit and inventory network devices to identify all Tenda M3 routers running the affected firmware version 1.0.0.12. 6. Engage with Tenda support channels to obtain or request firmware updates or patches addressing this vulnerability. 7. If patching is not immediately available, consider replacing vulnerable devices with more secure alternatives. 8. Educate network administrators about the vulnerability and encourage rapid response to alerts related to this CVE. 9. Implement network-level rate limiting and geo-blocking to reduce exposure to remote exploitation attempts from untrusted sources.