CVE-2022-49062 is a vulnerability identified in the Linux kernel's cachefiles module, specifically within the function cachefiles_set_volume_xattr. The flaw involves a slab-out-of-bounds write detected by the Kernel Address Sanitizer (KASAN). The root cause is the improper use of the length of volume coherency data when setting extended attributes (xattr), leading to a write operation that exceeds the allocated memory boundary by 4 bytes. This memory corruption occurs within a small 8-byte kmalloc slab object, indicating a critical boundary violation. The vulnerability manifests during the execution of the fscache_create_volume_work worker thread, which manages cache volumes. The out-of-bounds write can potentially corrupt kernel memory, leading to undefined behavior such as system crashes, data corruption, or privilege escalation. While no known exploits are currently reported in the wild, the nature of the bug—kernel memory corruption—makes it a significant security concern. The issue affects Linux kernel versions identified by the commit hash 413a4a6b0b5553f2423d210f65e98c211b99c3f8, and it was publicly disclosed on February 26, 2025. The vulnerability does not require user interaction but does require kernel-level execution context, typically triggered by kernel worker threads managing cachefiles. The patch involves correctly using the actual length of the volume coherency data to prevent the out-of-bounds write, thereby eliminating the KASAN slab violation.

For European organizations, this vulnerability poses a risk primarily to systems running affected Linux kernel versions with the cachefiles module enabled. Given Linux's widespread use in servers, cloud infrastructure, and embedded devices across Europe, exploitation could lead to kernel crashes, denial of service, or potentially privilege escalation if attackers can trigger the vulnerable code path. This could disrupt critical services, especially in sectors relying heavily on Linux-based infrastructure such as finance, telecommunications, government, and manufacturing. The risk is heightened in environments where kernel modules like cachefiles are actively used for caching network filesystems or similar workloads. Although no active exploits are known, the potential for kernel memory corruption means attackers with local access or the ability to execute code at kernel level could leverage this flaw to compromise system integrity and availability. This could result in operational downtime, data loss, or unauthorized access, impacting compliance with European data protection regulations and operational resilience requirements.

European organizations should prioritize updating their Linux kernels to versions that include the patch for CVE-2022-49062. Specifically, applying the official kernel updates that correct the length handling in cachefiles_set_volume_xattr is essential. Systems that do not require the cachefiles module should consider disabling it to reduce the attack surface. Additionally, organizations should implement strict access controls to limit who can load kernel modules or execute code with elevated privileges, reducing the risk of exploitation. Employing kernel hardening techniques such as Kernel Address Sanitizer (KASAN) in testing environments can help detect similar issues proactively. Monitoring kernel logs for KASAN reports or unusual cachefiles activity can provide early warning signs. For critical infrastructure, consider deploying intrusion detection systems capable of identifying anomalous kernel behavior. Finally, maintain a robust patch management process to ensure timely deployment of security updates across all Linux-based systems.