FKIE_CVE-2021-3492
Vulnerability from fkie_nvd - Published: 2021-04-17 05:15 - Updated: 2026-06-17 04:05
Severity
8.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.8 (High) - CVSS:3.1/
Summary
Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562.
References
Impacted products
| Vendor | Product | Version | |
|---|---|---|---|
| canonical | ubuntu_linux | * | |
| canonical | ubuntu_linux | * | |
| canonical | ubuntu_linux | * |
{
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{
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"status": "affected",
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},
{
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"status": "affected",
"version": "5.4 kernel",
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}
]
}
],
"source": "security@ubuntu.com"
}
],
"configurations": [
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"value": "Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562."
},
{
"lang": "es",
"value": "Shiftfs, un sistema de archivos de apilamiento fuera del \u00e1rbol incluido en los kernels de Ubuntu Linux, no manejaba apropiadamente los fallos que ocurr\u00edan durante la funci\u00f3n copy_from_user().\u0026#xa0;Esto podr\u00eda conllevar a una situaci\u00f3n de doble liberaci\u00f3n o a que la memoria no sea liberada del todo.\u0026#xa0;Un atacante podr\u00eda usar esto para causar una denegaci\u00f3n de servicio (agotamiento de la memoria del kernel) u alcanzar privilegios por medio de la ejecuci\u00f3n de c\u00f3digo arbitrario.\u0026#xa0;Tambi\u00e9n se conoce como ZDI-CAN-13562"
}
],
"id": "CVE-2021-3492",
"lastModified": "2026-06-17T04:05:12.033",
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"published": "2021-04-17T05:15:13.113",
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}
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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