CVE-2025-9961 is a high-severity buffer overflow vulnerability (CWE-120) affecting multiple versions of TP-Link Systems Inc.'s AX10 and AX1500 router models. The flaw exists in the CWMP (CPE WAN Management Protocol) binary component of these devices. Specifically, the vulnerability arises from a classic buffer copy operation that does not properly check the size of input data, allowing an authenticated attacker to remotely execute arbitrary code on the affected device. Exploitation requires a Man-In-The-Middle (MITM) attack vector, meaning the attacker must intercept and manipulate network traffic between the management server and the device. The affected AX10 versions include V1, V1.2, V2, V2.6, V3, and V3.6 with firmware versions prior to 1.2.1, and the AX1500 versions include V1, V1.20, V1.26, V1.60, V1.80, V2.60, and V3.6 with firmware versions prior to 1.3.11. The vulnerability has a CVSS 4.0 base score of 8.6, indicating high severity, with network attack vector, low attack complexity, no user interaction, but requiring high privileges (authenticated attacker). The impact scope is high on confidentiality, integrity, and availability, as arbitrary code execution can lead to full device compromise. No known exploits are currently reported in the wild, and no official patches or mitigation links were provided at the time of publication. This vulnerability poses a significant risk to network infrastructure relying on these TP-Link devices, especially in environments where CWMP management traffic is not adequately protected or monitored.

For European organizations, this vulnerability presents a critical risk to network security and operational continuity. TP-Link routers such as the AX10 and AX1500 are commonly deployed in small to medium enterprise networks and home office environments across Europe. Successful exploitation could allow attackers to gain persistent control over network gateways, enabling interception or manipulation of traffic, lateral movement within internal networks, and potential disruption of internet connectivity. Confidential data traversing these routers could be exposed or altered, undermining data privacy and regulatory compliance (e.g., GDPR). The requirement for a MITM attack suggests that organizations with insufficient network segmentation or lacking encrypted management protocols are particularly vulnerable. Additionally, the need for authentication implies insider threats or compromised credentials could facilitate exploitation. The absence of known exploits currently provides a window for proactive mitigation, but the high severity score underscores the urgency for European entities to address this vulnerability promptly to prevent potential targeted attacks or supply chain compromises.

European organizations should implement the following specific mitigation steps: 1) Immediately identify and inventory all TP-Link AX10 and AX1500 devices in their network environments, including firmware versions. 2) Apply firmware updates to versions 1.2.1 or later for AX10 models and 1.3.11 or later for AX1500 models as soon as official patches become available from TP-Link. 3) Until patches are applied, restrict access to CWMP management interfaces by implementing network segmentation and firewall rules that limit management traffic to trusted hosts only. 4) Employ strong authentication mechanisms and rotate credentials used for device management to reduce the risk of credential compromise. 5) Deploy network monitoring and intrusion detection systems capable of identifying anomalous CWMP traffic indicative of MITM attempts or exploitation activities. 6) Use encrypted management protocols (e.g., TLS) for CWMP communications where supported to prevent interception and manipulation. 7) Conduct regular security audits and penetration testing focused on network infrastructure devices to detect potential exploitation attempts early. 8) Educate IT staff about this vulnerability and the importance of securing device management channels. These targeted actions go beyond generic advice by focusing on the specific attack vector and device management protocols involved.