CVE-2025-60688 is a stack-based buffer overflow vulnerability identified in the ToToLink LR1200GB (firmware V9.1.0u.6619_B20230130) and NR1800X (firmware V9.1.0u.6681_B20230703) routers. The flaw exists in the cstecgi.cgi binary, specifically within the setDefResponse function, which processes the "IpAddress" parameter from incoming HTTP requests. The vulnerability stems from the use of the unsafe strcpy() function to copy the IpAddress parameter into a fixed-size stack buffer without validating the input length. This lack of bounds checking allows an attacker to supply a specially crafted input that overflows the buffer, potentially overwriting adjacent memory on the stack. Such memory corruption can lead to arbitrary code execution or cause the device to crash, resulting in denial of service. Notably, exploitation does not require any authentication or user interaction, meaning an attacker can trigger the vulnerability remotely over the network simply by sending a malicious HTTP request to the router's web interface. The CVSS v3.1 base score is 6.5, indicating a medium severity vulnerability with network attack vector, low attack complexity, no privileges required, no user interaction, unchanged scope, limited confidentiality impact, no integrity impact, and low availability impact. No public exploits or patches are currently available. The vulnerability is classified under CWE-121 (stack-based buffer overflow). Given the nature of the flaw, attackers could leverage it to gain control over the router, disrupt network connectivity, or use the compromised device as a foothold for further attacks within the network.

For European organizations, this vulnerability poses a moderate risk primarily to network infrastructure relying on ToToLink LR1200GB and NR1800X routers. Successful exploitation could allow attackers to execute arbitrary code on the router, potentially leading to full device compromise. This could result in interception or manipulation of network traffic, disruption of internet connectivity, and loss of availability for critical services. Attackers might also use compromised routers as pivot points to launch further attacks against internal systems or to establish persistent access. The lack of authentication requirement lowers the barrier for exploitation, increasing risk especially for routers exposed to untrusted networks or the internet. While the confidentiality impact is rated low, the availability impact could affect business continuity. European enterprises with remote or branch offices using these devices, as well as critical infrastructure operators, could face operational disruptions and increased exposure to cyber espionage or sabotage. The absence of known exploits in the wild currently reduces immediate risk but does not preclude future active exploitation.

Given the absence of official patches, European organizations should implement compensating controls to mitigate risk. First, restrict access to the router's web management interface by limiting it to trusted internal networks and disabling remote management over the internet. Employ network segmentation and firewall rules to block unauthorized traffic targeting the cstecgi.cgi endpoint. Monitor network traffic for anomalous HTTP requests containing suspicious IpAddress parameters or unusual payload sizes. Consider deploying intrusion detection/prevention systems (IDS/IPS) with custom signatures to detect exploitation attempts. Regularly audit router firmware versions and vendor advisories for updates or patches addressing this vulnerability. If possible, replace affected devices with models from vendors with timely security support. Additionally, enforce strong network perimeter defenses and maintain comprehensive logging to facilitate incident response. Educate network administrators about the vulnerability and encourage prompt reporting of any unusual router behavior or crashes.