CVE-2024-53147 is a vulnerability identified in the Linux kernel's exFAT filesystem driver. The flaw arises when the directory size is greater than or equal to the cluster size, and due to file system corruption, the start cluster (start_clu) becomes an EOF cluster, which is an invalid cluster. This invalid cluster leads to an out-of-bounds access when the directory entry index (ei->hint_femp.eidx) points outside the directory boundary. Such out-of-bounds access can cause further file system corruption, potentially leading to data integrity issues or system instability. The vulnerability is addressed by adding a validation check for start_clu; if it is detected as invalid, the file or directory is treated as empty, preventing the out-of-bounds access. This fix mitigates the risk of corruption propagation caused by malformed or corrupted exFAT filesystem structures. The vulnerability affects Linux kernel versions prior to the patch commit referenced by the hash 1acf1a564b6034b5af1e7fb23cb98cb3bb4f6003. There are no known exploits in the wild at the time of publication, and no CVSS score has been assigned yet.

For European organizations, this vulnerability could have significant implications, especially for those relying on Linux systems that utilize exFAT-formatted storage devices. exFAT is commonly used for removable media such as USB drives and SD cards, which are frequently exchanged in enterprise environments. An attacker or a corrupted device could trigger the vulnerability by introducing malformed directory entries, leading to file system corruption. This could result in data loss, system crashes, or denial of service conditions on critical Linux servers or workstations. Organizations in sectors such as finance, manufacturing, and public administration that depend on Linux infrastructure for data processing and storage could face operational disruptions. Moreover, since exFAT is often used for cross-platform compatibility, the risk extends to environments where Linux systems interact with Windows or macOS devices, increasing the attack surface. Although no active exploits are known, the potential for data integrity compromise and system instability necessitates prompt attention.

To mitigate this vulnerability, European organizations should: 1) Apply the latest Linux kernel updates that include the patch for CVE-2024-53147 as soon as they become available. 2) Implement strict controls on the use of removable media, including scanning and validating exFAT-formatted devices before connecting them to critical Linux systems. 3) Employ filesystem integrity monitoring tools to detect early signs of corruption or abnormal filesystem behavior. 4) Educate users on the risks of using untrusted external storage devices and enforce policies restricting their use. 5) Consider using alternative filesystems with robust journaling and error recovery features for critical data storage where feasible. 6) Regularly back up important data to enable recovery in case of corruption. These steps go beyond generic advice by focusing on filesystem-specific controls and operational practices tailored to the nature of the vulnerability.