CVE-2024-50293 is a vulnerability identified in the Linux kernel, specifically within the net/smc (Shared Memory Communications) subsystem. The issue arises in the __smc_create() function, where a dangling socket pointer (sock->sk) is not properly cleared upon failure during socket creation. This improper handling can lead to a use-after-free or dangling pointer condition, which may cause kernel instability or potentially allow an attacker to execute arbitrary code or escalate privileges. The vulnerability was discovered through syzbot, an automated kernel fuzzer, which detected that the socket creation function for the AF_SMC (Address Family Shared Memory Communications) protocol family does not clear the socket's sk pointer on failure, violating expected kernel socket lifecycle management. The kernel stack trace and debugging information indicate the failure occurs in __sock_create at net/socket.c line 1563, with the root cause being that the pf->create() function does not clear sock->sk on failure as required. The vulnerability affects Linux kernel versions prior to the patch that merged commit 2d859aff775d, which ensures that dangling sk pointers are not left in pf_create functions. Although no CVSS score has been assigned yet, the vulnerability is significant because it involves kernel-level socket management, a critical component of the operating system's networking stack. Exploitation would require triggering socket creation failures in the AF_SMC protocol, which is less commonly used but present in Linux kernels. No known exploits are currently reported in the wild, and the issue was responsibly disclosed and patched promptly.

For European organizations, the impact of CVE-2024-50293 could be substantial, particularly for those running Linux-based infrastructure, including servers, cloud environments, and embedded systems that utilize the affected kernel versions. The vulnerability could lead to kernel crashes (denial of service), which disrupt critical services and applications. More severe exploitation might allow attackers to execute arbitrary code with kernel privileges or escalate their privileges, compromising system confidentiality, integrity, and availability. This is especially concerning for sectors relying heavily on Linux servers such as finance, telecommunications, government, and critical infrastructure. Given the kernel-level nature of the flaw, successful exploitation could allow attackers to bypass many security controls, persist undetected, and move laterally within networks. However, the requirement to exploit a failure in AF_SMC socket creation limits the attack surface somewhat, as AF_SMC is not widely used compared to other socket families. Nonetheless, organizations using specialized Linux configurations or custom networking stacks should be vigilant. The lack of known exploits in the wild reduces immediate risk but does not eliminate the need for urgent remediation to prevent future attacks.

European organizations should take the following specific mitigation steps: 1) Immediately identify Linux systems running kernel versions prior to the patch that merged commit 2d859aff775d, focusing on those using or potentially using the AF_SMC protocol. 2) Apply the latest Linux kernel updates or patches that address CVE-2024-50293 as soon as they become available from trusted Linux distributions or kernel maintainers. 3) For systems where immediate patching is not feasible, consider disabling or restricting the use of the AF_SMC protocol family if it is not required, to reduce the attack surface. 4) Implement kernel hardening features such as Kernel Address Space Layout Randomization (KASLR), Kernel Page Table Isolation (KPTI), and seccomp filters to limit the impact of potential kernel exploits. 5) Monitor system logs and kernel messages for unusual socket creation failures or crashes that could indicate attempted exploitation. 6) Employ intrusion detection systems capable of detecting anomalous kernel behavior or privilege escalation attempts. 7) Conduct thorough testing of kernel updates in staging environments to ensure stability before deployment in production. These targeted actions go beyond generic advice by focusing on the specific subsystem and attack vector involved in this vulnerability.