CVE-2025-9248 is a high-severity stack-based buffer overflow vulnerability affecting multiple Linksys range extender models, including RE6250, RE6300, RE6350, RE6500, RE7000, and RE9000, across several firmware versions (1.0.013.001, 1.0.04.001, 1.0.04.002, 1.1.05.003, and 1.2.07.001). The vulnerability resides in the function RP_pingGatewayByBBS within the /goform/RP_pingGatewayByBBS endpoint. Specifically, the vulnerability is triggered by improper handling of the 'ssidhex' argument, which leads to a stack-based buffer overflow condition. This flaw allows an attacker to remotely execute arbitrary code or cause a denial of service without requiring user interaction or authentication. The CVSS 4.0 base score of 8.7 reflects the critical nature of this vulnerability, with network attack vector, low attack complexity, no privileges or user interaction required, and high impact on confidentiality, integrity, and availability. Although the vendor was notified early, no patch or response has been issued, and a public exploit is available, increasing the risk of exploitation. The vulnerability affects the firmware's network-facing interface, making it accessible remotely, which significantly raises the threat level. Exploitation could allow attackers to take full control of the affected devices, potentially pivoting into internal networks or disrupting network connectivity.

For European organizations, this vulnerability poses a significant risk, especially for enterprises and service providers using Linksys range extenders in their network infrastructure. Successful exploitation could lead to unauthorized access to internal networks, data exfiltration, or disruption of network services through denial of service attacks. Given that these devices often extend wireless coverage in offices, retail locations, or industrial environments, compromise could facilitate lateral movement within corporate networks or impact operational technology systems. The lack of vendor response and available public exploits increases the likelihood of active exploitation attempts. Additionally, the vulnerability could be leveraged by threat actors to establish persistent footholds or launch further attacks against critical infrastructure or sensitive data repositories. The impact extends beyond confidentiality to integrity and availability, potentially causing widespread operational disruptions. Organizations relying on these devices without timely mitigation are at elevated risk of cyber espionage, ransomware, or sabotage campaigns.

Immediate mitigation steps include isolating affected devices from critical network segments and restricting remote access to management interfaces. Network administrators should implement strict firewall rules to block inbound traffic to the vulnerable endpoint (/goform/RP_pingGatewayByBBS) and monitor network traffic for suspicious activity targeting these devices. Since no official patches are available, organizations should consider replacing vulnerable Linksys extenders with updated or alternative hardware from vendors with active security support. Employing network segmentation to limit the exposure of these devices and deploying intrusion detection/prevention systems (IDS/IPS) tuned to detect exploitation attempts can reduce risk. Regularly auditing device firmware versions and configurations, combined with enhanced logging and alerting, will help identify potential compromise early. Organizations should also prepare incident response plans specific to IoT and network device breaches. Engaging with Linksys support channels and monitoring for future patches or advisories is critical for long-term remediation.