{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-50115", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-10-21T19:36:19.947Z", "datePublished": "2024-11-05T17:10:46.677Z", "dateUpdated": "2026-08-05T11:41:45.626Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:41:45.626Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: nSVM: Ignore nCR3[4:0] when loading PDPTEs from memory\n\nIgnore nCR3[4:0] when loading PDPTEs from memory for nested SVM, as bits\n4:0 of CR3 are ignored when PAE paging is used, and thus VMRUN doesn't\nenforce 32-byte alignment of nCR3.\n\nIn the absolute worst case scenario, failure to ignore bits 4:0 can result\nin an out-of-bounds read, e.g. if the target page is at the end of a\nmemslot, and the VMM isn't using guard pages.\n\nPer the APM:\n\n The CR3 register points to the base address of the page-directory-pointer\n table. The page-directory-pointer table is aligned on a 32-byte boundary,\n with the low 5 address bits 4:0 assumed to be 0.\n\nAnd the SDM's much more explicit:\n\n 4:0 Ignored\n\nNote, KVM gets this right when loading PDPTRs, it's only the nSVM flow\nthat is broken." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:H", "baseScore": 8.4, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The attacker must execute code on the host machine, specifically CPL0 inside an L1 guest, issuing VMRUN with an attacker-chosen nCR3; there is no network protocol involved. Guest-to-host attacks against KVM are scored as local access to the host.\nAC:L - Every precondition is under the attacker's control — L1 chooses 32-bit PAE mode, sets the NPT enable bit, and sets nCR3[4:0]; nested SVM and NPT are enabled by default in kvm_amd, and nCR3 receives no alignment validation, so the out-of-bounds read triggers deterministically on the first VMRUN. The guest knows its own e820 map and can aim at a memslot-terminating gfn and retry against every memslot boundary.\nPR:L - The attacker needs kernel-level (CPL0) control of a guest VM whose CPUID exposes SVM — i.e. an ordinary tenant VM on a nested-virtualization-enabled AMD host, which is a low privilege level relative to the host kernel being attacked. No host-side root or /dev/kvm privileges beyond running one's own VM are required.\nUI:N - Exploitation is entirely driven by instructions the attacker executes in its own guest; no host administrator or other user needs to take any action.\nS:C - The vulnerable component is KVM in the host kernel, but the impacted resource is host VMM process memory lying outside the guest's memslot, so the attack crosses the guest/host security boundary. This is the classic KVM guest-to-host scope change.\nC:H - Up to 31 bytes past the end of every memslot in the host VMM's address space can be read, and the value is recoverable by the guest through the shadow-NPT root oracle in mmu_alloc_shadow_roots(), disclosing host heap contents and pointers that defeat host ASLR. It is repeatable at each memslot boundary, so it is not strictly bounded to a few bytes at one fixed location.\nI:N - The defect is purely a read; the resulting PDPTE only influences translations that remain gated by kvm_vcpu_is_visible_gfn() and normal memslot lookup, and any accessed/dirty writes land in the attacker's own L1 memory. No host memory is corrupted and no control-flow primitive is produced.\nA:H - In affected v6.12-rc1..rc4 kernels the same guest-controlled offset trips the WARN_ON_ONCE(offset + len > PAGE_SIZE) hardening check in __kvm_read_guest_page(), giving a guest-triggerable host kernel WARN that panics the entire host — and all co-resident VMs — on the widely used panic_on_warn=1 configuration." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "arch/x86/kvm/svm/nested.c" ], "versions": [ { "version": "e4e517b4be019787ada4cbbce2f04570c21b0cbd", "lessThan": "76ce386feb14ec9a460784fcd495d8432acce7a5", "status": "affected", "versionType": "git" }, { "version": "e4e517b4be019787ada4cbbce2f04570c21b0cbd", "lessThan": "58cb697d80e669c56197f703e188867c8c54c494", "status": "affected", "versionType": "git" }, { "version": "e4e517b4be019787ada4cbbce2f04570c21b0cbd", "lessThan": "6876793907cbe19d42e9edc8c3315a21e06c32ae", "status": "affected", "versionType": "git" }, { "version": "e4e517b4be019787ada4cbbce2f04570c21b0cbd", "lessThan": "2c4adc9b192a0815fe58a62bc0709449416cc884", "status": "affected", "versionType": "git" }, { "version": "e4e517b4be019787ada4cbbce2f04570c21b0cbd", "lessThan": "426682afec71ea3f889b972d038238807b9443e4", "status": "affected", "versionType": "git" }, { "version": "e4e517b4be019787ada4cbbce2f04570c21b0cbd", "lessThan": "f559b2e9c5c5308850544ab59396b7d53cfc67bd", "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/svm/nested.c" ], "versions": [ { "version": "3.2", "status": "affected" }, { "version": "0", "lessThan": "3.2", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.229", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.170", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.115", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.59", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.11.6", "lessThanOrEqual": "6.11.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12", "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": "3.2", "versionEndExcluding": "5.10.229" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.2", "versionEndExcluding": "5.15.170" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.2", "versionEndExcluding": "6.1.115" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.2", "versionEndExcluding": "6.6.59" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.2", "versionEndExcluding": "6.11.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.2", "versionEndExcluding": "6.12" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/76ce386feb14ec9a460784fcd495d8432acce7a5" }, { "url": "https://git.kernel.org/stable/c/58cb697d80e669c56197f703e188867c8c54c494" }, { "url": "https://git.kernel.org/stable/c/6876793907cbe19d42e9edc8c3315a21e06c32ae" }, { "url": "https://git.kernel.org/stable/c/2c4adc9b192a0815fe58a62bc0709449416cc884" }, { "url": "https://git.kernel.org/stable/c/426682afec71ea3f889b972d038238807b9443e4" }, { "url": "https://git.kernel.org/stable/c/f559b2e9c5c5308850544ab59396b7d53cfc67bd" } ], "title": "KVM: nSVM: Ignore nCR3[4:0] when loading PDPTEs from memory", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "cvssV3_1": { "scope": "UNCHANGED", "version": "3.1", "baseScore": 7.1, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH" } }, { "other": { "type": "ssvc", "content": { "id": "CVE-2024-50115", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2025-10-01T20:21:56.032296Z" } } } ], "problemTypes": [ { "descriptions": [ { "lang": "en", "type": "CWE", "cweId": "CWE-125", "description": "CWE-125 Out-of-bounds Read" } ] } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2025-10-01T20:27:17.080Z" } }, { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html" }, { "url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T22:25:38.622Z" } } ] } }