A firmware node allocated on the stack or heap with a non‑zeroing allocator and initialized by fwnode_init() leaves the fwnode_handle->secondary pointer uninitialized. When an API later dereferences this pointer, such as dev_to_swnode(), the kernel can crash or exhibit undefined behavior, leading to a denial‑of‑service condition.

All Linux kernel releases that have not incorporated the commit that sets fwnode_handle->secondary to NULL and fully initializes the structure are potentially affected. The exact version range is not specified, so any kernel lacking this patch is at risk.

Based on the description, the vulnerability requires creation or manipulation of a firmware node, which typically occurs only in kernel code or drivers. Therefore the likely attack vector is local exploitation through malicious kernel modules or firmware. The CVSS score of 7.8 indicates high severity, while the EPSS score of < 1% shows exploitation probability is low. The vulnerability is not listed in the CISA KEV catalog, indicating no publicly known exploits exist. However, if triggered, the uninitialized secondary pointer can be dereferenced by functions such as dev_to_swnode(), potentially leading to a kernel crash or undefined behavior that can disrupt availability.