CVE-2021-47255

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Prior to commit 01402cf81051 (\"kvm: LAPIC:\nwrite down valid APIC registers\"), such an access was explicitly\ndisallowed. Restore the guard that was removed in that commit."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: kvm: LAPIC: Restaurar protecci\u00f3n para evitar el acceso ilegal al registro APIC. Seg\u00fan el SDM, \"cualquier acceso que toque los bytes 4 al 15 de un registro APIC puede causar un comportamiento indefinido y no debe ejecutarse \". Peor a\u00fan, dicho acceso en kvm_lapic_reg_read puede resultar en una fuga del contenido de la pila del kernel. Antes de confirmar 01402cf81051 (\"kvm: LAPIC: anotar registros APIC v\u00e1lidos\"), dicho acceso se prohib\u00eda expl\u00edcitamente. 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{"bugzilla": {"description": "kernel: kvm: LAPIC: Restore guard to prevent illegal APIC register access", "id": "2282555", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2282555"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.1", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:L", "status": "draft"}, "cwe": "CWE-402", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nkvm: LAPIC: Restore guard to prevent illegal APIC register access\nPer the SDM, \"any access that touches bytes 4 through 15 of an APIC\nregister may cause undefined behavior and must not be executed.\"\nWorse, such an access in kvm_lapic_reg_read can result in a leak of\nkernel stack contents. Prior to commit 01402cf81051 (\"kvm: LAPIC:\nwrite down valid APIC registers\"), such an access was explicitly\ndisallowed. Restore the guard that was removed in that commit."], "name": "CVE-2021-47255", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2024-05-21T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2021-47255\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-47255\nhttps://lore.kernel.org/linux-cve-announce/2024052146-CVE-2021-47255-c840@gregkh/T"], "threat_severity": "Low"}

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