CVE-2026-52973

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> futex: Drop CLONE_THREAD requirement for private default hash alloc<br /> <br /> Currently need_futex_hash_allocate_default() depends on strict pthread<br /> semantics, abusing CLONE_THREAD. This breaks the non-concurrency<br /> assumptions when doing the mm-&gt;futex_ref pcpu allocations, leading to<br /> bugs[0] when sharing the mm in other ways; ie:<br /> <br /> BUG: KASAN: slab-use-after-free in futex_hash_put<br /> <br /> ... where the +1 bias can end up on a percpu counter that mm-&gt;futex_ref<br /> no longer points at.<br /> <br /> Loosen the check to cover any CLONE_VM clone, except vfork(). Excluding<br /> vfork keeps the existing paths untouched (no overhead), and we can&amp;#39;t<br /> race in the first place: either the parent is suspended and the child<br /> runs alone, or mm-&gt;futex_ref is already allocated from an earlier<br /> CLONE_VM.