CVE-2026-74593
In the Linux kernel, the following vulnerability has been resolved:
sched_ext: Take cgroup_lock() first in scx_cgroup_lock()
scx_cgroup_lock() write-locks scx_cgroup_ops_rwsem and then takes cgroup_lock(), which can deadlock through kernfs:
The enable path waits for the rmdir to release cgroup_mutex. The rmdir, deactivating the cpu controller's files, waits in kernfs_drain() for the write's active reference. The write, in scx_group_set_weight(), waits for the rwsem behind the pending writer.
Take cgroup_lock() first. The set_* paths take no cgroup locks inside the read side, so a pending write-lock then only waits for read sections that always run to completion, and no dependency from the rwsem back to cgroup_mutex remains.
Detalles técnicos trazas, registros y código del informe original
scx enable/disable cgroup rmdir cpu.weight write
------------------ ------------ ----------------
cgroup_lock()
percpu_down_write(rwsem)
cgroup_lock()
kernfs_get_active()
percpu_down_read(rwsem)
kernfs_drain()CVSS
NVD no ha asignado puntuación CVSS a esta CVE (habitual desde el cambio de política de abril de 2026).
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.21%
- Percentil entre todas las CVEs puntuadas: 10
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-74593",
"cveTags": [],
"metrics": {},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "a5bd6ba30b3364354269b81ac55c2edca9a96d6d",
"lessThan": "2ca6b43edf83f8fc368cc3094ee5f3b1e8e0b0f0",
"versionType": "git"
},
{
"status": "affected",
"version": "a5bd6ba30b3364354269b81ac55c2edca9a96d6d",
"lessThan": "a054c9ffa9b7a0dffb763837b91ac9d381ec6d10",
"versionType": "git"
},
{
"status": "affected",
"version": "a5bd6ba30b3364354269b81ac55c2edca9a96d6d",
"lessThan": "5f8b69642d18e1f3e11996707842ac530444e959",
"versionType": "git"
}
],
"programFiles": [
"kernel/sched/ext/ext.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.18"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.18",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.18.46",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.9",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"kernel/sched/ext/ext.c"
],
"defaultStatus": "affected"
}
]
}
],
"published": "2026-08-22T16:16:31.573",
"references": [
{
"url": "https://git.kernel.org/stable/c/2ca6b43edf83f8fc368cc3094ee5f3b1e8e0b0f0",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/5f8b69642d18e1f3e11996707842ac530444e959",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/a054c9ffa9b7a0dffb763837b91ac9d381ec6d10",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"vulnStatus": "Received",
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsched_ext: Take cgroup_lock() first in scx_cgroup_lock()\n\nscx_cgroup_lock() write-locks scx_cgroup_ops_rwsem and then takes\ncgroup_lock(), which can deadlock through kernfs:\n\n scx enable/disable cgroup rmdir cpu.weight write\n ------------------ ------------ ----------------\n cgroup_lock()\n percpu_down_write(rwsem)\n cgroup_lock()\n kernfs_get_active()\n percpu_down_read(rwsem)\n kernfs_drain()\n\nThe enable path waits for the rmdir to release cgroup_mutex. The rmdir,\ndeactivating the cpu controller's files, waits in kernfs_drain() for the\nwrite's active reference. The write, in scx_group_set_weight(), waits for\nthe rwsem behind the pending writer.\n\nTake cgroup_lock() first. The set_* paths take no cgroup locks inside the\nread side, so a pending write-lock then only waits for read sections that\nalways run to completion, and no dependency from the rwsem back to\ncgroup_mutex remains."
}
],
"lastModified": "2026-08-23T13:16:45.993",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}