Vulnerability-Lookup

GHSA-9QJ4-WR4G-7M6F

Vulnerability from github – Published: 2026-06-24 18:32 – Updated: 2026-06-30 03:37

Details

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.

Severity

7.8 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2026-52973"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-825"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-24T17:17:07Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nfutex: Drop CLONE_THREAD requirement for private default hash alloc\n\nCurrently need_futex_hash_allocate_default() depends on strict pthread\nsemantics, abusing CLONE_THREAD.  This breaks the non-concurrency\nassumptions when doing the mm-\u003efutex_ref pcpu allocations, leading to\nbugs[0] when sharing the mm in other ways; ie:\n\n    BUG: KASAN: slab-use-after-free in futex_hash_put\n\n... where the +1 bias can end up on a percpu counter that mm-\u003efutex_ref\nno longer points at.\n\nLoosen the check to cover any CLONE_VM clone, except vfork().  Excluding\nvfork keeps the existing paths untouched (no overhead), and we can\u0027t\nrace in the first place: either the parent is suspended and the child\nruns alone, or mm-\u003efutex_ref is already allocated from an earlier\nCLONE_VM.",
  "id": "GHSA-9qj4-wr4g-7m6f",
  "modified": "2026-06-30T03:37:12Z",
  "published": "2026-06-24T18:32:42Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-52973"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-52973"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2492413"
    },
    {
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    },
    {
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      "url": "https://git.kernel.org/stable/c/974ac49a9a068b0591a59f65c63eb06579a13091"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ee9dce44362b2d8132c32964656ab6dff7dfbc6a"
    },
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      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-52973 (GCVE-0-2026-52973)

Vulnerability from cvelistv5 – Published: 2026-06-24 16:28 – Updated: 2026-06-30 12:09

Title

futex: Drop CLONE_THREAD requirement for private default hash alloc

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.

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

7 (High)


                        
                          CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

CWE

CWE-825 - Expired Pointer Dereference

Assigner

Linux

References

6 references

URL	Tags
https://git.kernel.org/stable/c/1dcd36420af2da5bd…
https://git.kernel.org/stable/c/974ac49a9a068b059…
https://git.kernel.org/stable/c/ee9dce44362b2d813…
https://access.redhat.com/security/cve/CVE-2026-52973	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2492413	issue-trackingx_refsource_REDHAT
https://security.access.redhat.com/data/csaf/v2/v…	x_sadp-csaf-vex

Impacted products

7 products

Vendor	Product	Version
Linux	Linux	Affected: d9b05321e21e4b218de4ce8a590bf375f58b6346 , < 1dcd36420af2da5bd59306dba9caf78e3d248b1d (git) Affected: d9b05321e21e4b218de4ce8a590bf375f58b6346 , < 974ac49a9a068b0591a59f65c63eb06579a13091 (git) Affected: d9b05321e21e4b218de4ce8a590bf375f58b6346 , < ee9dce44362b2d8132c32964656ab6dff7dfbc6a (git)
Linux	Linux	Affected: 6.17 Unaffected: 0 , < 6.17 (semver) Unaffected: 6.18.33 , ≤ 6.18.* (semver) Unaffected: 7.0.10 , ≤ 7.0.* (semver) Unaffected: 7.1 , ≤ * (original_commit_for_fix)
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7
Red Hat	Red Hat Enterprise Linux 8	cpe:/o:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:enterprise_linux:6

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-9QJ4-WR4G-7M6F

CVE-2026-52973 (GCVE-0-2026-52973)

Tags

Sightings

Nomenclature