CVE-2026-23316

A flaw was found in the Linux kernel's handling of multipath hash seeds on ARM64 architectures. This vulnerability can lead to a system crash (kernel panic) when the kernel is compiled with specific optimizations, such as Clang with Link-Time Optimization (LTO), due to an alignment fault during memory access. Additionally, a separate issue exists where non-atomic updates to the hash seed can result in a tear-write vulnerability, potentially compromising data integrity. These issues could be triggered under specific conditions related to network multipath hashing.

This flaw is specific to ARM64 systems running kernels compiled with Clang LTO. The alignment fault occurs when READ_ONCE() on a 4-byte aligned 8-byte structure causes a 64-bit Load-Acquire instruction to execute on a misaligned address. Additionally, the tear-write vulnerability affects atomicity of hash seed updates. Most enterprise deployments use GCC-compiled kernels where this specific issue does not manifest.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.