CVE-2026-52973
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.
Affected versions
Linux kernel versions
6.17
and later are affected. Fixed in
6.18.33,
7.0.10,
7.1
and their respective stable series.
References
3 totalFrequently asked questions
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What is CVE-2026-52973?
CVE-2026-52973 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 6.17 onward and has been patched in 6.18.33, 7.0.10 and 7.1. CVE-2026-52973 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-52973?
Yes — CVE-2026-52973 has been patched. Fixed versions include 6.18.33, 7.0.10 and 7.1. If you are running Linux kernel 6.17 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-52973 actively exploited?
No — CVE-2026-52973 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.