CVE-2024-36958 is a vulnerability identified in the Linux kernel's NFS server implementation, specifically within the nfsd4_encode_fattr4() function. This function is responsible for encoding file attributes in the NFSv4 protocol. The vulnerability arises because the args.acl variable is not properly initialized early in the function. Since args.acl is used unconditionally in a call to kfree() (kernel memory free function) on the function's exit path, this can lead to a use-after-free or double-free condition, causing the kernel to crash (kernel panic) or potentially enabling further exploitation. The root cause is a failure to initialize a pointer before it is freed, which is a classic memory management error. The fix involves ensuring args.acl is initialized early to prevent invalid memory deallocation. Although no known exploits are reported in the wild at this time, the vulnerability affects Linux kernels that include the vulnerable NFS server code. Given that NFS is widely used for network file sharing in enterprise and cloud environments, this flaw could be leveraged by an attacker with network access to the NFS server to cause denial of service (DoS) or potentially escalate privileges if combined with other vulnerabilities. The vulnerability does not require user interaction but does require access to the NFS server functionality. No CVSS score is assigned yet, and no patch links are provided in the data, but the issue is publicly disclosed and marked as resolved in recent kernel updates.

For European organizations, the impact of CVE-2024-36958 could be significant, especially for those relying on Linux-based NFS servers for critical file sharing and storage infrastructure. A successful exploitation could cause kernel crashes leading to denial of service, disrupting business operations, data availability, and potentially impacting services dependent on shared file systems. In environments where NFS servers are exposed to untrusted networks or where strict network segmentation is not enforced, attackers could remotely trigger this vulnerability. Although no direct evidence of privilege escalation is currently known, kernel crashes can be leveraged as a stepping stone in multi-stage attacks. The disruption could affect sectors such as finance, manufacturing, research institutions, and government agencies that rely heavily on Linux servers for file sharing. Additionally, cloud service providers and data centers operating Linux-based infrastructure in Europe could face service interruptions or increased operational risk if vulnerable systems are not patched promptly.

To mitigate CVE-2024-36958, European organizations should: 1) Immediately identify and inventory Linux systems running NFS server functionality, particularly those exposed to external or untrusted networks. 2) Apply the latest Linux kernel patches or updates that address this vulnerability as soon as they become available from trusted Linux distributions or kernel maintainers. 3) If immediate patching is not feasible, consider disabling NFSv4 server functionality temporarily or restricting access to the NFS server via network segmentation and firewall rules to trusted hosts only. 4) Monitor system logs and kernel crash reports for signs of exploitation attempts or abnormal behavior related to nfsd4_encode_fattr4(). 5) Implement strict access controls and network-level protections to limit exposure of NFS services. 6) Conduct vulnerability scanning and penetration testing focused on NFS services to detect potential exploitation vectors. 7) Maintain an incident response plan that includes procedures for kernel-level crashes and service restoration. These steps go beyond generic advice by focusing on the specific vulnerable component and its operational context.