CVE-2026-52973 (GCVE-0-2026-52973)
Vulnerability from cvelistv5
Published
2026-06-24 16:28
Modified
2026-09-03 12:04
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: futex: Drop CLONE_THREAD requirement for private default hash alloc Currently need_futex_hash_allocate_default() depends on strict pthread semantics, abusing CLONE_THREAD. This breaks the non-concurrency assumptions when doing the mm->futex_ref pcpu allocations, leading to bugs[0] when sharing the mm in other ways; ie: BUG: KASAN: slab-use-after-free in futex_hash_put ... where the +1 bias can end up on a percpu counter that mm->futex_ref no longer points at. Loosen the check to cover any CLONE_VM clone, except vfork(). Excluding vfork keeps the existing paths untouched (no overhead), and we can't race in the first place: either the parent is suspended and the child runs alone, or mm->futex_ref is already allocated from an earlier CLONE_VM.
References
Impacted products
Vendor Product Version
Linux Linux Version: d9b05321e21e4b218de4ce8a590bf375f58b6346
Version: d9b05321e21e4b218de4ce8a590bf375f58b6346
Version: d9b05321e21e4b218de4ce8a590bf375f58b6346
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