Refcount Vulnerability in Linux Kernel's AFS File System

CVE-2026-46100

What is CVE-2026-46100?

A refcount vulnerability in the AFS file system of the Linux kernel allows for refcount increments to leak during allocation failures or merges. This situation arises because the .mmap_prepare() function is invoked in a context where a failure may occur after the refcount is increased, thus failing to properly manage memory references. The Linux kernel has addressed this issue by partially reverting a previous commit, establishing the need for careful handling of memory references in asynchronous operations.

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