CVE-2024-46677 is a vulnerability identified in the Linux kernel's GPRS Tunneling Protocol (GTP) implementation. Specifically, the flaw arises in the function gtp_encap_enable_socket(), which is responsible for enabling socket encapsulation for GTP. When the internal function sockfd_lookup() fails, gtp_encap_enable_socket() returns a NULL pointer. However, the callers of this function only check for error pointers and do not handle the NULL pointer case properly. This oversight can lead to a NULL pointer dereference when the returned pointer is used without validation. The consequence of a NULL pointer dereference in kernel space is typically a kernel panic or system crash, resulting in a denial of service (DoS). The vulnerability was discovered during code inspection and has been fixed by modifying gtp_encap_enable_socket() to return an error pointer carrying the error code from sockfd_lookup(), ensuring that callers can correctly detect and handle the failure scenario. The affected versions are identified by a specific commit hash repeated multiple times, indicating a particular code state in the Linux kernel source. There are no known exploits in the wild at the time of publication, and no CVSS score has been assigned yet. The vulnerability affects the Linux kernel, which is widely used across many distributions and devices, especially those involved in telecommunications infrastructure that utilize GTP for mobile data tunneling.

For European organizations, the impact of CVE-2024-46677 primarily revolves around potential denial of service conditions on Linux systems that utilize the GTP protocol stack. Telecommunications providers, mobile network operators, and infrastructure vendors in Europe that deploy Linux-based systems for 4G/5G core network components or other GTP-dependent services are at particular risk. A successful exploitation could cause kernel crashes, leading to service interruptions or outages, which can degrade network availability and reliability. Enterprises relying on Linux servers for critical applications that interface with mobile networks or use GTP encapsulation might also experience disruptions. While this vulnerability does not directly lead to privilege escalation or data compromise, the resulting downtime could affect business continuity, customer experience, and regulatory compliance, especially under stringent EU data protection and service availability requirements. Given the widespread use of Linux in European IT environments, the vulnerability's impact could extend to cloud providers, hosting services, and industrial control systems that incorporate GTP functionality.

To mitigate this vulnerability, European organizations should promptly apply the official Linux kernel patches that address CVE-2024-46677 once they become available from their Linux distribution vendors. Since the issue involves kernel-level code, updating to a patched kernel version is critical. Organizations should: 1) Identify all systems running affected Linux kernel versions with GTP support enabled, particularly those involved in telecommunications or mobile data processing. 2) Coordinate with vendors and distribution maintainers to obtain and deploy updated kernel packages. 3) In environments where immediate patching is not feasible, consider temporarily disabling GTP encapsulation features if operationally possible to reduce exposure. 4) Monitor system logs and kernel crash reports for signs of NULL pointer dereference or unexpected reboots that could indicate exploitation attempts or triggering of the vulnerability. 5) Implement robust network segmentation and access controls to limit exposure of vulnerable systems to untrusted networks, reducing the risk of remote triggering. 6) Engage with telecom equipment vendors to confirm their products are patched or not affected. 7) Maintain an incident response plan to quickly address potential service disruptions caused by this vulnerability.