CVE-2026-49428
Full vulnerability record from the local CVENow database.
Description
Certain system calls, such open(2) with the O_TRUNC flag set, and fspacectl(2), could incorrectly free memory in largepage objects. These operations are not permitted on largepage objects, but the implementation did not verify this. An unprivileged local user can abuse the bug to access freed kernel memory. This can be exploited to escalate privileges.
Severity
HIGH
CVSS score
8.4
(v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-08-19 06:17:42.263000
Last modified
2026-11-09 20:10:00.200000
View original CVE JSON
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"id": "CVE-2026-49428",
"sourceIdentifier": "[email protected]",
"published": "2026-08-19T06:17:42.263",
"lastModified": "2026-11-09T20:10:00.200",
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"value": "Certain system calls, such open(2) with the O_TRUNC flag set, and fspacectl(2), could incorrectly free memory in largepage objects. These operations are not permitted on largepage objects, but the implementation did not verify this.\n\nAn unprivileged local user can abuse the bug to access freed kernel memory. This can be exploited to escalate privileges."
},
{
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"value": "Ciertas llamadas al sistema, como open(2) con el indicador O_TRUNC establecido, y fspacectl(2), podrían liberar memoria incorrectamente en objetos de página grande. Estas operaciones no están permitidas en objetos de página grande, pero la implementación no verificó esto.\n\nUn usuario local sin privilegios puede abusar del error para acceder a memoria del kernel liberada. Esto puede ser explotado para escalar privilegios."
}
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{
"source": "[email protected]",
"affectedData": [
{
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"product": "FreeBSD",
"defaultStatus": "unknown",
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"references": [
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"source": "[email protected]",
"tags": [
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}