CVE-2024-45023 is a vulnerability identified in the Linux kernel's md/raid1 subsystem, which manages RAID 1 arrays. RAID 1 arrays mirror data across multiple disks to provide redundancy and fault tolerance. The vulnerability arises from a logic flaw in the read balancing mechanism when operating with degraded arrays that include slow or recovering disks. Specifically, the function choose_bb_rdev() lacks proper checks to determine whether a disk is still in recovery before selecting it as the source for read operations. This can lead to the system reading unrecovered or stale data from a disk that has not yet fully synchronized, causing data corruption. The issue also affects choose_slow_rdev(), which similarly misses recovery state checks. The root cause is that the recovery status of disks is not properly verified before read requests are routed, allowing potentially invalid data to be returned to the system. The patch involves adding recovery state checks to these functions to prevent reading from disks that are not fully recovered. This vulnerability is particularly critical in environments relying on RAID 1 for data integrity and availability, as it undermines the fundamental guarantee of mirrored data consistency. Although no known exploits are reported in the wild, the flaw could lead to silent data corruption, which is difficult to detect and can have severe consequences for data reliability.

For European organizations, especially those in sectors such as finance, healthcare, government, and critical infrastructure that rely heavily on Linux-based systems with RAID 1 configurations, this vulnerability poses a significant risk. Data corruption in RAID 1 arrays can lead to loss of data integrity, potentially causing operational disruptions, erroneous decision-making, and compliance violations under regulations like GDPR that mandate data accuracy and integrity. Since RAID 1 is often used to ensure high availability and fault tolerance, this flaw could also impact system availability if corrupted data leads to system crashes or necessitates recovery procedures. The silent nature of the corruption increases the risk of prolonged undetected data integrity issues, which can cascade into broader system failures or data loss incidents. Organizations using Linux kernels with affected versions should be particularly vigilant, as the vulnerability affects the core kernel RAID subsystem, which is widely deployed across servers and enterprise systems in Europe.

To mitigate this vulnerability, European organizations should prioritize updating their Linux kernel to the patched version that includes the fix for CVE-2024-45023. Since the vulnerability involves kernel-level RAID management, patching is the most effective measure. Additionally, organizations should: 1) Audit their systems to identify any RAID 1 arrays, especially those with slow or recovering disks, and monitor their health status closely. 2) Implement enhanced monitoring and alerting for RAID array degradation and recovery states to detect anomalies early. 3) Perform integrity checks on critical data stored on RAID 1 arrays to identify potential corruption. 4) Consider temporary operational adjustments such as avoiding reliance on slow or degraded disks until recovery completes. 5) Maintain robust backup and recovery procedures to restore data in case corruption is detected. 6) Test patches in staging environments to ensure compatibility and stability before deployment in production. These steps go beyond generic advice by focusing on RAID-specific operational practices and proactive data integrity verification.