futex: Drop CLONE_THREAD requirement for private default hash alloc
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.
CVE-2026-52973
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-52973
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "d9b05321e21e4b218de4ce8a590bf375f58b6346",
"lessThan": "1dcd36420af2da5bd59306dba9caf78e3d248b1d",
"versionType": "git"
},
{
"status": "affected",
"version": "d9b05321e21e4b218de4ce8a590bf375f58b6346",
"lessThan": "974ac49a9a068b0591a59f65c63eb06579a13091",
"versionType": "git"
},
{
"status": "affected",
"version": "d9b05321e21e4b218de4ce8a590bf375f58b6346",
"lessThan": "ee9dce44362b2d8132c32964656ab6dff7dfbc6a",
"versionType": "git"
}
],
"programFiles": [
"kernel/fork.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.17"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.17",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.18.33",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.0.10",
"versionType": "semver",
"lessThanOrEqual": "7.0.*"
},
{
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"kernel/fork.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-52973
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #40717 · Revision 1
- Added to Heist Feed
- Publisher date