CVE-2021-4159
Full vulnerability record from the local CVENow database.
Description
A vulnerability was found in the Linux kernel's EBPF verifier when handling internal data structures. Internal memory locations could be returned to userspace. A local attacker with the permissions to insert eBPF code to the kernel can use this to leak internal kernel memory details defeating some of the exploit mitigations in place for the kernel.
Severity
MEDIUM
CVSS score
4.4
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2022-08-24 16:15:09.713000
Last modified
2026-11-02 19:17:46.043000
View original CVE JSON
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"id": "CVE-2021-4159",
"sourceIdentifier": "[email protected]",
"published": "2022-08-24T16:15:09.713",
"lastModified": "2026-11-02T19:17:46.043",
"vulnStatus": "Modified",
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"lang": "en",
"value": "A vulnerability was found in the Linux kernel's EBPF verifier when handling internal data structures. Internal memory locations could be returned to userspace. A local attacker with the permissions to insert eBPF code to the kernel can use this to leak internal kernel memory details defeating some of the exploit mitigations in place for the kernel."
},
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"value": "Se encontró una vulnerabilidad en el verificador EBPF del kernel de Linux cuando son manejadas estructuras de datos internas. Las ubicaciones de memoria interna podían ser devueltas al espacio de usuario. Un atacante local con permisos para insertar código eBPF en el kernel puede usar esto para filtrar detalles de la memoria interna del kernel derrotando algunas de las mitigaciones de explotación en el lugar para el kernel."
}
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"affected": [
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"source": "[email protected]",
"affectedData": [
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"vendor": "n/a",
"product": "kernel",
"versions": [
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"version": "Fixed in v5.7-rc1",
"status": "affected"
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"baseScore": 4.4,
"baseSeverity": "MEDIUM",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "HIGH",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "NONE",
"availabilityImpact": "NONE"
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