CVE-2025-9006 is a high-severity buffer overflow vulnerability found in the Tenda CH22 router, specifically version 1.0.0.1. The flaw exists in the function formdelFileName within the /goform/delFileName endpoint. This endpoint is accessible remotely, allowing an attacker to send specially crafted requests that overflow a buffer in memory. Buffer overflow vulnerabilities can lead to arbitrary code execution, denial of service, or system crashes. The vulnerability requires no user interaction and no authentication, making it remotely exploitable over the network. The CVSS 4.0 base score is 8.7, reflecting the ease of exploitation (network attack vector, low attack complexity), no privileges required, and no user interaction needed. The impact on confidentiality, integrity, and availability is high, as successful exploitation could allow an attacker to execute arbitrary code with elevated privileges on the device, potentially taking full control of the router. Although no public exploits are currently known to be in the wild, the exploit code has been disclosed publicly, increasing the risk of imminent attacks. The vulnerability affects only the specific firmware version 1.0.0.1 of the Tenda CH22, a consumer-grade router model. No official patches or mitigation links have been provided yet, indicating that affected users must rely on other defensive measures until a vendor fix is released.

For European organizations, the exploitation of this vulnerability could have significant consequences. Routers like the Tenda CH22 are often used in small office/home office (SOHO) environments and by smaller enterprises. Compromise of these devices can lead to network traffic interception, man-in-the-middle attacks, or pivoting into internal networks. This is particularly concerning for organizations with remote or distributed workforces relying on such routers for connectivity. The high severity and remote exploitability mean attackers could gain persistent access to network infrastructure, potentially exfiltrating sensitive data or disrupting business operations. Additionally, compromised routers could be enlisted into botnets, amplifying broader cyber threats. The lack of patches increases exposure time, and public exploit disclosure heightens the urgency for mitigation. European organizations with limited IT security resources may be disproportionately affected due to reliance on consumer-grade networking equipment.

1. Immediate network segmentation: Isolate Tenda CH22 devices from critical internal networks to limit lateral movement if compromised. 2. Disable or restrict remote management interfaces on the router to prevent external exploitation of the vulnerable endpoint. 3. Monitor network traffic for unusual patterns or signs of exploitation attempts targeting /goform/delFileName. 4. Employ intrusion detection/prevention systems (IDS/IPS) with signatures for this vulnerability once available. 5. Replace or upgrade affected devices to models with vendor-supported, patched firmware as soon as updates are released. 6. If patching is not immediately possible, consider deploying firewall rules to block access to the vulnerable endpoint or restrict access to trusted IPs only. 7. Educate users and administrators about the risks of using outdated firmware and the importance of timely updates. 8. Regularly audit network devices to identify and inventory vulnerable hardware for prioritized remediation.