CVE-2026-49427
Full vulnerability record from the local CVENow database.
Description
Pages belonging to largepage shared memory objects were not explicitly wired. When sendfile(2) transmitted such an object with the SF_NOCACHE flag, it freed the underlying pages after transmission even though existing mappings still referred to them. An unprivileged local user can abuse the bug to access freed kernel memory. This can be exploited to escalate privileges.
Severity
HIGH
CVSS score
8.8
(v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-08-19 06:17:41.977000
Last modified
2026-11-09 20:10:00.200000
View original CVE JSON
{
"id": "CVE-2026-49427",
"sourceIdentifier": "[email protected]",
"published": "2026-08-19T06:17:41.977",
"lastModified": "2026-11-09T20:10:00.200",
"vulnStatus": "Analyzed",
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"value": "Pages belonging to largepage shared memory objects were not explicitly wired. When sendfile(2) transmitted such an object with the SF_NOCACHE flag, it freed the underlying pages after transmission even though existing mappings still referred to them.\n\nAn unprivileged local user can abuse the bug to access freed kernel memory. This can be exploited to escalate privileges."
},
{
"lang": "es",
"value": "Páginas pertenecientes a objetos de memoria compartida de páginas grandes no estaban cableadas explícitamente. Cuando sendfile(2) transmitía dicho objeto con la bandera SF_NOCACHE, liberaba las páginas subyacentes después de la transmisión aunque las asignaciones existentes aún se referían a ellas.\n\nUn usuario local sin privilegios puede abusar del error para acceder a memoria del kernel liberada. Esto puede ser explotado para escalar privilegios."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "FreeBSD",
"product": "FreeBSD",
"defaultStatus": "unknown",
"modules": [
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"userInteraction": "NONE",
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"references": [
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"source": "[email protected]",
"tags": [
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}