CVE-2025-46836 is a medium-severity vulnerability affecting the net-tools package, a foundational set of Linux networking utilities including ifconfig, widely used for network interface configuration and management. The vulnerability arises from improper input validation in the function get_name() within interface.c, which processes interface labels read from the /proc/net/dev file. Specifically, the function copies these labels into a fixed-size 16-byte stack buffer without performing bounds checking, leading to a classic stack-based buffer overflow (CWE-121) caused by improper input validation (CWE-20). This flaw can be triggered by crafting malicious entries in /proc/net/dev, potentially allowing an attacker to cause a denial of service (crash) or execute arbitrary code within the context of the affected utility. Notably, exploitation does not require elevated privileges, but the vulnerability does not provide privilege escalation by itself. The CVSS v3.1 score is 6.6, reflecting a medium severity with local attack vector, low attack complexity, low privileges required, no user interaction, and impacts on confidentiality, integrity, and availability. A patch is available and expected in net-tools version 2.20, while versions up to and including 2.10 remain vulnerable. No known exploits are currently reported in the wild. The vulnerability is significant because net-tools remains installed by default or as a legacy tool on many Linux distributions, especially in server and embedded environments, making it a relevant risk for systems relying on these utilities for network management.

For European organizations, the impact of this vulnerability can be substantial in environments where net-tools is used for network configuration and monitoring, particularly on legacy or embedded Linux systems that have not migrated to newer tools like iproute2. Successful exploitation could lead to arbitrary code execution or service crashes, potentially disrupting network management operations and causing downtime. Although the vulnerability does not grant privilege escalation, an attacker with local access (such as through compromised user accounts or insider threats) could leverage this flaw to execute malicious code, potentially facilitating lateral movement or persistence. Critical infrastructure operators, telecommunications providers, and enterprises with Linux-based network appliances or servers are particularly at risk. The disruption of network utilities could impair incident response and network troubleshooting efforts, increasing operational risk. Additionally, the medium severity and local attack vector imply that attackers need some level of system access, which may limit exposure but does not eliminate risk, especially in multi-user or shared environments.

European organizations should prioritize upgrading net-tools to version 2.20 or later, which includes the patch addressing this vulnerability. In environments where immediate upgrading is not feasible, organizations should restrict local access to systems running vulnerable net-tools versions, enforcing strict user permissions and monitoring for unusual activity related to network utilities. Employing host-based intrusion detection systems (HIDS) to detect anomalous behavior or crashes of network tools can provide early warning of exploitation attempts. Additionally, organizations should consider migrating to more modern network management tools such as iproute2, which do not exhibit this vulnerability. Regularly auditing and hardening Linux systems to minimize local user privileges and applying comprehensive endpoint security controls will reduce the attack surface. Network segmentation and limiting access to critical systems can further mitigate risk. Finally, maintaining up-to-date backups and incident response plans will help organizations recover quickly if exploitation occurs.