CVE-2021-47390

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2021-47390", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-05-21T14:58:30.813Z", "datePublished": "2024-05-21T15:03:48.883Z", "dateUpdated": "2026-08-05T08:47:35.643Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T08:47:35.643Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()\n\nKASAN reports the following issue:\n\n BUG: KASAN: stack-out-of-bounds in kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n Read of size 8 at addr ffffc9001364f638 by task qemu-kvm/4798\n\n CPU: 0 PID: 4798 Comm: qemu-kvm Tainted: G X --------- ---\n Hardware name: AMD Corporation DAYTONA_X/DAYTONA_X, BIOS RYM0081C 07/13/2020\n Call Trace:\n dump_stack+0xa5/0xe6\n print_address_description.constprop.0+0x18/0x130\n ? kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n __kasan_report.cold+0x7f/0x114\n ? kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n kasan_report+0x38/0x50\n kasan_check_range+0xf5/0x1d0\n kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n kvm_make_scan_ioapic_request_mask+0x84/0xc0 [kvm]\n ? kvm_arch_exit+0x110/0x110 [kvm]\n ? sched_clock+0x5/0x10\n ioapic_write_indirect+0x59f/0x9e0 [kvm]\n ? static_obj+0xc0/0xc0\n ? __lock_acquired+0x1d2/0x8c0\n ? kvm_ioapic_eoi_inject_work+0x120/0x120 [kvm]\n\nThe problem appears to be that 'vcpu_bitmap' is allocated as a single long\non stack and it should really be KVM_MAX_VCPUS long. We also seem to clear\nthe lower 16 bits of it with bitmap_zero() for no particular reason (my\nguess would be that 'bitmap' and 'vcpu_bitmap' variables in\nkvm_bitmap_or_dest_vcpus() caused the confusion: while the later is indeed\n16-bit long, the later should accommodate all possible vCPUs)."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH"}, "scenarios": [{"lang": "en", "value": "AV:L - The bug is reached when a guest writes the in-kernel IOAPIC MMIO window (0xfec00000), causing a KVM MMIO exit into ioapic_mmio_write \u2192 ioapic_write_indirect on the host; this is a local hypervisor/guest interface, not a network protocol path.\nAC:L - A guest (or VMM user who creates the VM) can reliably trigger the path by writing an IOAPIC redirect entry with FIXED delivery mode; the undersized bitmap is always over-read, and with \u226565 vCPUs the attacker-controlled dest can also force out-of-bounds __set_bit writes with no race or uncontrolled condition.\nPR:L - Exploitation needs only the ability to run a KVM guest that uses the in-kernel irqchip\u2014typically an unprivileged kvm-group user on /dev/kvm, or a cloud tenant controlling their guest OS\u2014not real host root/CAP_SYS_ADMIN.\nUI:N - No victim action is required; the attacker triggers the vulnerable IOAPIC write path directly from guest code or their own VMM once the VM exists.\nS:C - A malicious guest corrupts host-kernel stack memory in KVM\u2019s IOAPIC emulation, crossing the guest/host security boundary and enabling a potential VM escape affecting the host and other tenants.\nC:H - kvm_make_vcpus_request_mask performs a stack out-of-bounds read of the undersized vcpu_bitmap across KVM_MAX_VCPUS bits (~128 bytes), and stack corruption from the related OOB write can be leveraged for further host memory disclosure.\nI:H - kvm_bitmap_or_dest_vcpus uses __set_bit() on vcpu_idx values that can exceed the single unsigned long (bits \u226564), writing past the stack allocation toward higher stack addresses and enabling host memory corruption / control-flow hijacking.\nA:H - The out-of-bounds stack access can oops/panic the host kernel (as shown by the KASAN report in qemu-kvm), so availability impact on the host is high."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["arch/x86/kvm/ioapic.c"], "versions": [{"version": "7ee30bc132c683d06a6d9e360e39e483e3990708", "lessThan": "bebabb76ad9acca8858e0371e102fb60d708e25b", "status": "affected", "versionType": "git"}, {"version": "7ee30bc132c683d06a6d9e360e39e483e3990708", "lessThan": "99a9e9b80f19fc63be005a33d76211dd23114792", "status": "affected", "versionType": "git"}, {"version": "7ee30bc132c683d06a6d9e360e39e483e3990708", "lessThan": "2f9b68f57c6278c322793a06063181deded0ad69", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["arch/x86/kvm/ioapic.c"], "versions": [{"version": "5.5", "status": "affected"}, {"version": "0", "lessThan": "5.5", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.71", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.14.10", "lessThanOrEqual": "5.14.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "5.10.71"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "5.14.10"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "5.15"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/bebabb76ad9acca8858e0371e102fb60d708e25b"}, {"url": "https://git.kernel.org/stable/c/99a9e9b80f19fc63be005a33d76211dd23114792"}, {"url": "https://git.kernel.org/stable/c/2f9b68f57c6278c322793a06063181deded0ad69"}], "title": "KVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2024-06-17T17:37:17.652949Z", "id": "CVE-2021-47390", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-06-17T17:38:01.491Z"}}, {"providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-04T05:39:59.812Z"}, "title": "CVE Program Container", "references": [{"url": "https://git.kernel.org/stable/c/bebabb76ad9acca8858e0371e102fb60d708e25b", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/99a9e9b80f19fc63be005a33d76211dd23114792", "tags": ["x_transferred"]}, {"url": "https://git.kernel.org/stable/c/2f9b68f57c6278c322793a06063181deded0ad69", "tags": ["x_transferred"]}]}]}}

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this is a local hypervisor/guest interface, not a network protocol path.\nAC:L - A guest (or VMM user who creates the VM) can reliably trigger the path by writing an IOAPIC redirect entry with FIXED delivery mode; the undersized bitmap is always over-read, and with \u226565 vCPUs the attacker-controlled dest can also force out-of-bounds __set_bit writes with no race or uncontrolled condition.\nPR:L - Exploitation needs only the ability to run a KVM guest that uses the in-kernel irqchip\u2014typically an unprivileged kvm-group user on /dev/kvm, or a cloud tenant controlling their guest OS\u2014not real host root/CAP_SYS_ADMIN.\nUI:N - No victim action is required; the attacker triggers the vulnerable IOAPIC write path directly from guest code or their own VMM once the VM exists.\nS:C - A malicious guest corrupts host-kernel stack memory in KVM\u2019s IOAPIC emulation, crossing the guest/host security boundary and enabling a potential VM escape affecting the host and other tenants.\nC:H - kvm_make_vcpus_request_mask performs a stack out-of-bounds read of the undersized vcpu_bitmap across KVM_MAX_VCPUS bits (~128 bytes), and stack corruption from the related OOB write can be leveraged for further host memory disclosure.\nI:H - kvm_bitmap_or_dest_vcpus uses __set_bit() on vcpu_idx values that can exceed the single unsigned long (bits \u226564), writing past the stack allocation toward higher stack addresses and enabling host memory corruption / control-flow hijacking.\nA:H - The out-of-bounds stack access can oops/panic the host kernel (as shown by the KASAN report in qemu-kvm), so availability impact on the host is high."}]}], "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "7ee30bc132c683d06a6d9e360e39e483e3990708", "lessThan": "bebabb76ad9acca8858e0371e102fb60d708e25b", "versionType": "git"}, {"status": "affected", "version": "7ee30bc132c683d06a6d9e360e39e483e3990708", "lessThan": "99a9e9b80f19fc63be005a33d76211dd23114792", "versionType": "git"}, {"status": "affected", "version": "7ee30bc132c683d06a6d9e360e39e483e3990708", "lessThan": "2f9b68f57c6278c322793a06063181deded0ad69", "versionType": "git"}], "programFiles": ["arch/x86/kvm/ioapic.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5.5"}, {"status": "unaffected", "version": "0", "lessThan": "5.5", "versionType": "semver"}, {"status": "unaffected", "version": "5.10.71", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "5.14.10", "versionType": "semver", "lessThanOrEqual": "5.14.*"}, {"status": "unaffected", "version": "5.15", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["arch/x86/kvm/ioapic.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/bebabb76ad9acca8858e0371e102fb60d708e25b"}, {"url": "https://git.kernel.org/stable/c/99a9e9b80f19fc63be005a33d76211dd23114792"}, {"url": "https://git.kernel.org/stable/c/2f9b68f57c6278c322793a06063181deded0ad69"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()\n\nKASAN reports the following issue:\n\n BUG: KASAN: stack-out-of-bounds in kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n Read of size 8 at addr ffffc9001364f638 by task qemu-kvm/4798\n\n CPU: 0 PID: 4798 Comm: qemu-kvm Tainted: G X --------- ---\n Hardware name: AMD Corporation DAYTONA_X/DAYTONA_X, BIOS RYM0081C 07/13/2020\n Call Trace:\n dump_stack+0xa5/0xe6\n print_address_description.constprop.0+0x18/0x130\n ? kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n __kasan_report.cold+0x7f/0x114\n ? kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n kasan_report+0x38/0x50\n kasan_check_range+0xf5/0x1d0\n kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n kvm_make_scan_ioapic_request_mask+0x84/0xc0 [kvm]\n ? kvm_arch_exit+0x110/0x110 [kvm]\n ? sched_clock+0x5/0x10\n ioapic_write_indirect+0x59f/0x9e0 [kvm]\n ? static_obj+0xc0/0xc0\n ? __lock_acquired+0x1d2/0x8c0\n ? kvm_ioapic_eoi_inject_work+0x120/0x120 [kvm]\n\nThe problem appears to be that 'vcpu_bitmap' is allocated as a single long\non stack and it should really be KVM_MAX_VCPUS long. We also seem to clear\nthe lower 16 bits of it with bitmap_zero() for no particular reason (my\nguess would be that 'bitmap' and 'vcpu_bitmap' variables in\nkvm_bitmap_or_dest_vcpus() caused the confusion: while the later is indeed\n16-bit long, the later should accommodate all possible vCPUs)."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.10.71", "versionStartIncluding": "5.5"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.14.10", "versionStartIncluding": "5.5"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "5.15", "versionStartIncluding": "5.5"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T08:47:35.643Z"}}}, "cveMetadata": {"cveId": "CVE-2021-47390", "state": "PUBLISHED", "dateUpdated": "2026-08-05T08:47:35.643Z", "dateReserved": "2024-05-21T14:58:30.813Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2024-05-21T15:03:48.883Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["arch/x86/kvm/ioapic.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "bebabb76ad9acca8858e0371e102fb60d708e25b", "status": "affected", "version": "7ee30bc132c683d06a6d9e360e39e483e3990708", "versionType": "git"}, {"lessThan": "99a9e9b80f19fc63be005a33d76211dd23114792", "status": "affected", "version": "7ee30bc132c683d06a6d9e360e39e483e3990708", "versionType": "git"}, {"lessThan": "2f9b68f57c6278c322793a06063181deded0ad69", "status": "affected", "version": "7ee30bc132c683d06a6d9e360e39e483e3990708", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["arch/x86/kvm/ioapic.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.5"}, {"lessThan": "5.5", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.71", "versionType": "semver"}, {"lessThanOrEqual": "5.14.*", "status": "unaffected", "version": "5.14.10", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "5.15", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "60C740E4-6C54-40CD-A914-2232D8FC781D", "versionEndExcluding": "5.10.71", "versionStartIncluding": "5.5", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "1A437B0D-8305-4C72-B691-D26986A126CF", "versionEndExcluding": "5.14.10", "versionStartIncluding": "5.11", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc1:*:*:*:*:*:*", "matchCriteriaId": "E46C74C6-B76B-4C94-A6A4-FD2FFF62D644", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc2:*:*:*:*:*:*", "matchCriteriaId": "60134C3A-06E4-48C1-B04F-2903732A4E56", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:5.15:rc3:*:*:*:*:*:*", "matchCriteriaId": "0460DA88-8FE1-46A2-9DDA-1F1ABA552E71", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()\n\nKASAN reports the following issue:\n\n BUG: KASAN: stack-out-of-bounds in kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n Read of size 8 at addr ffffc9001364f638 by task qemu-kvm/4798\n\n CPU: 0 PID: 4798 Comm: qemu-kvm Tainted: G X --------- ---\n Hardware name: AMD Corporation DAYTONA_X/DAYTONA_X, BIOS RYM0081C 07/13/2020\n Call Trace:\n dump_stack+0xa5/0xe6\n print_address_description.constprop.0+0x18/0x130\n ? kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n __kasan_report.cold+0x7f/0x114\n ? kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n kasan_report+0x38/0x50\n kasan_check_range+0xf5/0x1d0\n kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n kvm_make_scan_ioapic_request_mask+0x84/0xc0 [kvm]\n ? kvm_arch_exit+0x110/0x110 [kvm]\n ? sched_clock+0x5/0x10\n ioapic_write_indirect+0x59f/0x9e0 [kvm]\n ? static_obj+0xc0/0xc0\n ? __lock_acquired+0x1d2/0x8c0\n ? kvm_ioapic_eoi_inject_work+0x120/0x120 [kvm]\n\nThe problem appears to be that 'vcpu_bitmap' is allocated as a single long\non stack and it should really be KVM_MAX_VCPUS long. We also seem to clear\nthe lower 16 bits of it with bitmap_zero() for no particular reason (my\nguess would be that 'bitmap' and 'vcpu_bitmap' variables in\nkvm_bitmap_or_dest_vcpus() caused the confusion: while the later is indeed\n16-bit long, the later should accommodate all possible vCPUs)."}, {"lang": "es", "value": "En el kernel de Linux, se resolvi\u00f3 la siguiente vulnerabilidad: KVM: x86: corrige el acceso a la memoria de pila fuera de los l\u00edmites desde ioapic_write_indirect() KASAN informa el siguiente problema: BUG: KASAN: pila fuera de los l\u00edmites en kvm_make_vcpus_request_mask+ 0x174/0x440 [kvm] Lectura de tama\u00f1o 8 en la direcci\u00f3n ffffc9001364f638 por tarea qemu-kvm/4798 CPU: 0 PID: 4798 Comm: qemu-kvm Contaminado: GX --------- --- Nombre de hardware: AMD Corporaci\u00f3n DAYTONA_X/DAYTONA_X, BIOS RYM0081C 13/07/2020 Seguimiento de llamadas: dump_stack+0xa5/0xe6 print_address_description.constprop.0+0x18/0x130 ? kvm_make_vcpus_request_mask+0x174/0x440 [kvm] __kasan_report.cold+0x7f/0x114 ? kvm_make_vcpus_request_mask+0x174/0x440 [kvm] kasan_report+0x38/0x50 kasan_check_range+0xf5/0x1d0 kvm_make_vcpus_request_mask+0x174/0x440 [kvm] 0 [kvm] ? kvm_arch_exit+0x110/0x110 [kvm] ? sched_clock+0x5/0x10 ioapic_write_indirect+0x59f/0x9e0 [kvm] ? static_obj+0xc0/0xc0? __lock_acquired+0x1d2/0x8c0? kvm_ioapic_eoi_inject_work+0x120/0x120 [kvm] El problema parece ser que 'vcpu_bitmap' est\u00e1 asignado como un \u00fanico largo en la pila y en realidad deber\u00eda ser KVM_MAX_VCPUS largo. Tambi\u00e9n parece que borramos los 16 bits inferiores con bitmap_zero() sin ning\u00fan motivo en particular (supongo que las variables 'bitmap' y 'vcpu_bitmap' en kvm_bitmap_or_dest_vcpus() causaron la confusi\u00f3n: mientras que la \u00faltima tiene 16 bits de longitud , este \u00faltimo deber\u00eda acomodar todas las vCPU posibles)."}], "id": "CVE-2021-47390", "lastModified": "2026-08-04T10:17:01.297", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 8.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 2.0, "impactScore": 6.0, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.1, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.2, "source": "nvd@nist.gov", "type": "Primary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2021-47390", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2024-06-17T17:37:17.652949Z", "version": "2.0.3"}}]}, "published": "2024-05-21T15:15:24.397", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/2f9b68f57c6278c322793a06063181deded0ad69"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/99a9e9b80f19fc63be005a33d76211dd23114792"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/bebabb76ad9acca8858e0371e102fb60d708e25b"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/2f9b68f57c6278c322793a06063181deded0ad69"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/99a9e9b80f19fc63be005a33d76211dd23114792"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/bebabb76ad9acca8858e0371e102fb60d708e25b"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-125"}], "source": "nvd@nist.gov", "type": "Primary"}]}

{"bugzilla": {"description": "kernel: KVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()", "id": "2282350", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2282350"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.1", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:H", "status": "draft"}, "cwe": "CWE-121", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nKVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()\nKASAN reports the following issue:\nBUG: KASAN: stack-out-of-bounds in kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\nRead of size 8 at addr ffffc9001364f638 by task qemu-kvm/4798\nCPU: 0 PID: 4798 Comm: qemu-kvm Tainted: G X --------- ---\nHardware name: AMD Corporation DAYTONA_X/DAYTONA_X, BIOS RYM0081C 07/13/2020\nCall Trace:\ndump_stack+0xa5/0xe6\nprint_address_description.constprop.0+0x18/0x130\n? kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n__kasan_report.cold+0x7f/0x114\n? kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\nkasan_report+0x38/0x50\nkasan_check_range+0xf5/0x1d0\nkvm_make_vcpus_request_mask+0x174/0x440 [kvm]\nkvm_make_scan_ioapic_request_mask+0x84/0xc0 [kvm]\n? kvm_arch_exit+0x110/0x110 [kvm]\n? sched_clock+0x5/0x10\nioapic_write_indirect+0x59f/0x9e0 [kvm]\n? static_obj+0xc0/0xc0\n? __lock_acquired+0x1d2/0x8c0\n? kvm_ioapic_eoi_inject_work+0x120/0x120 [kvm]\nThe problem appears to be that 'vcpu_bitmap' is allocated as a single long\non stack and it should really be KVM_MAX_VCPUS long. We also seem to clear\nthe lower 16 bits of it with bitmap_zero() for no particular reason (my\nguess would be that 'bitmap' and 'vcpu_bitmap' variables in\nkvm_bitmap_or_dest_vcpus() caused the confusion: while the later is indeed\n16-bit long, the later should accommodate all possible vCPUs)."], "mitigation": {"lang": "en:us", "value": "Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update the affected package as soon as possible."}, "name": "CVE-2021-47390", "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": "Not 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-2021-47390\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-47390\nhttps://lore.kernel.org/linux-cve-announce/2024052146-CVE-2021-47390-5f20@gregkh/T"], "statement": "This vulnerability is rated as a moderate severity because it impacting the reliability of virtual machine operations which does not directly facilitate arbitrary code execution or privilege escalation.", "threat_severity": "Moderate"}

{}