{"api_version":"1","generated_at":"2026-05-12T23:15:51+00:00","cve":"CVE-2026-43315","urls":{"html":"https://cve.report/CVE-2026-43315","api":"https://cve.report/api/cve/CVE-2026-43315.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-43315","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-43315"},"summary":{"title":"KVM: nSVM: Remove a user-triggerable WARN on nested_svm_load_cr3() succeeding","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: nSVM: Remove a user-triggerable WARN on nested_svm_load_cr3() succeeding\n\nDrop the WARN in svm_set_nested_state() on nested_svm_load_cr3() failing\nas it is trivially easy to trigger from userspace by modifying CPUID after\nloading CR3.  E.g. modifying the state restoration selftest like so:\n\n  --- tools/testing/selftests/kvm/x86/state_test.c\n  +++ tools/testing/selftests/kvm/x86/state_test.c\n  @@ -280,7 +280,16 @@ int main(int argc, char *argv[])\n\n                 /* Restore state in a new VM.  */\n                  vcpu = vm_recreate_with_one_vcpu(vm);\n  -               vcpu_load_state(vcpu, state);\n  +\n  +               if (stage == 4) {\n  +                       state->sregs.cr3 = BIT(44);\n  +                       vcpu_load_state(vcpu, state);\n  +\n  +                       vcpu_set_cpuid_property(vcpu, X86_PROPERTY_MAX_PHY_ADDR, 36);\n  +                       __vcpu_nested_state_set(vcpu, &state->nested);\n  +               } else {\n  +                       vcpu_load_state(vcpu, state);\n  +               }\n\n                  /*\n                   * Restore XSAVE state in a dummy vCPU, first without doing\n\ngenerates:\n\n  WARNING: CPU: 30 PID: 938 at arch/x86/kvm/svm/nested.c:1877 svm_set_nested_state+0x34a/0x360 [kvm_amd]\n  Modules linked in: kvm_amd kvm irqbypass [last unloaded: kvm]\n  CPU: 30 UID: 1000 PID: 938 Comm: state_test Tainted: G        W           6.18.0-rc7-58e10b63777d-next-vm\n  Tainted: [W]=WARN\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n  RIP: 0010:svm_set_nested_state+0x34a/0x360 [kvm_amd]\n  Call Trace:\n   <TASK>\n   kvm_arch_vcpu_ioctl+0xf33/0x1700 [kvm]\n   kvm_vcpu_ioctl+0x4e6/0x8f0 [kvm]\n   __x64_sys_ioctl+0x8f/0xd0\n   do_syscall_64+0x61/0xad0\n   entry_SYSCALL_64_after_hwframe+0x4b/0x53\n\nSimply delete the WARN instead of trying to prevent userspace from shoving\n\"illegal\" state into CR3.  For better or worse, KVM's ABI allows userspace\nto set CPUID after SREGS, and vice versa, and KVM is very permissive when\nit comes to guest CPUID.  I.e. attempting to enforce the virtual CPU model\nwhen setting CPUID could break userspace.  Given that the WARN doesn't\nprovide any meaningful protection for KVM or benefit for userspace, simply\ndrop it even though the odds of breaking userspace are minuscule.\n\nOpportunistically delete a spurious newline.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-05-08 14:16:39","updated_at":"2026-05-12 14:10:27"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/ebb2ab4f1c87d6b52776292cf7dc16aea48e95f8","name":"https://git.kernel.org/stable/c/ebb2ab4f1c87d6b52776292cf7dc16aea48e95f8","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/580ea57840864d40e019bc13fd26afdc8d510a2f","name":"https://git.kernel.org/stable/c/580ea57840864d40e019bc13fd26afdc8d510a2f","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/fc3ba56385d03501eb582e4b86691ba378e556f9","name":"https://git.kernel.org/stable/c/fc3ba56385d03501eb582e4b86691ba378e556f9","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/155ec243ef726f4bc49536fa0bfb565dc011ab17","name":"https://git.kernel.org/stable/c/155ec243ef726f4bc49536fa0bfb565dc011ab17","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/deb8f6dfd31d94b18dbeeaa8c01fbec5fc70fd2b","name":"https://git.kernel.org/stable/c/deb8f6dfd31d94b18dbeeaa8c01fbec5fc70fd2b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/ce904c8a5bbe697eae0f7e34b07095bd7a6dee19","name":"https://git.kernel.org/stable/c/ce904c8a5bbe697eae0f7e34b07095bd7a6dee19","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/969e5e13ff5c18603f21d1f9f64ec9194e141ac0","name":"https://git.kernel.org/stable/c/969e5e13ff5c18603f21d1f9f64ec9194e141ac0","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-43315","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-43315","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b222b0b88162bdef4eceb12a79d5edbbdb23dbfd 155ec243ef726f4bc49536fa0bfb565dc011ab17 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b222b0b88162bdef4eceb12a79d5edbbdb23dbfd 580ea57840864d40e019bc13fd26afdc8d510a2f git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b222b0b88162bdef4eceb12a79d5edbbdb23dbfd deb8f6dfd31d94b18dbeeaa8c01fbec5fc70fd2b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b222b0b88162bdef4eceb12a79d5edbbdb23dbfd ce904c8a5bbe697eae0f7e34b07095bd7a6dee19 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b222b0b88162bdef4eceb12a79d5edbbdb23dbfd 969e5e13ff5c18603f21d1f9f64ec9194e141ac0 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b222b0b88162bdef4eceb12a79d5edbbdb23dbfd ebb2ab4f1c87d6b52776292cf7dc16aea48e95f8 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected b222b0b88162bdef4eceb12a79d5edbbdb23dbfd fc3ba56385d03501eb582e4b86691ba378e556f9 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.14","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.14 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.15.202 5.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.165 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.128 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.75 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.16 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.19.6 6.19.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"43315","cve":"CVE-2026-43315","epss":"0.000240000","percentile":"0.070210000","score_date":"2026-05-11","updated_at":"2026-05-12 00:01:18"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["arch/x86/kvm/svm/nested.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"155ec243ef726f4bc49536fa0bfb565dc011ab17","status":"affected","version":"b222b0b88162bdef4eceb12a79d5edbbdb23dbfd","versionType":"git"},{"lessThan":"580ea57840864d40e019bc13fd26afdc8d510a2f","status":"affected","version":"b222b0b88162bdef4eceb12a79d5edbbdb23dbfd","versionType":"git"},{"lessThan":"deb8f6dfd31d94b18dbeeaa8c01fbec5fc70fd2b","status":"affected","version":"b222b0b88162bdef4eceb12a79d5edbbdb23dbfd","versionType":"git"},{"lessThan":"ce904c8a5bbe697eae0f7e34b07095bd7a6dee19","status":"affected","version":"b222b0b88162bdef4eceb12a79d5edbbdb23dbfd","versionType":"git"},{"lessThan":"969e5e13ff5c18603f21d1f9f64ec9194e141ac0","status":"affected","version":"b222b0b88162bdef4eceb12a79d5edbbdb23dbfd","versionType":"git"},{"lessThan":"ebb2ab4f1c87d6b52776292cf7dc16aea48e95f8","status":"affected","version":"b222b0b88162bdef4eceb12a79d5edbbdb23dbfd","versionType":"git"},{"lessThan":"fc3ba56385d03501eb582e4b86691ba378e556f9","status":"affected","version":"b222b0b88162bdef4eceb12a79d5edbbdb23dbfd","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["arch/x86/kvm/svm/nested.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.14"},{"lessThan":"5.14","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.202","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.165","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.128","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.75","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.16","versionType":"semver"},{"lessThanOrEqual":"6.19.*","status":"unaffected","version":"6.19.6","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.0","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.202","versionStartIncluding":"5.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.165","versionStartIncluding":"5.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.128","versionStartIncluding":"5.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.75","versionStartIncluding":"5.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.16","versionStartIncluding":"5.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.19.6","versionStartIncluding":"5.14","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0","versionStartIncluding":"5.14","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: nSVM: Remove a user-triggerable WARN on nested_svm_load_cr3() succeeding\n\nDrop the WARN in svm_set_nested_state() on nested_svm_load_cr3() failing\nas it is trivially easy to trigger from userspace by modifying CPUID after\nloading CR3.  E.g. modifying the state restoration selftest like so:\n\n  --- tools/testing/selftests/kvm/x86/state_test.c\n  +++ tools/testing/selftests/kvm/x86/state_test.c\n  @@ -280,7 +280,16 @@ int main(int argc, char *argv[])\n\n                 /* Restore state in a new VM.  */\n                  vcpu = vm_recreate_with_one_vcpu(vm);\n  -               vcpu_load_state(vcpu, state);\n  +\n  +               if (stage == 4) {\n  +                       state->sregs.cr3 = BIT(44);\n  +                       vcpu_load_state(vcpu, state);\n  +\n  +                       vcpu_set_cpuid_property(vcpu, X86_PROPERTY_MAX_PHY_ADDR, 36);\n  +                       __vcpu_nested_state_set(vcpu, &state->nested);\n  +               } else {\n  +                       vcpu_load_state(vcpu, state);\n  +               }\n\n                  /*\n                   * Restore XSAVE state in a dummy vCPU, first without doing\n\ngenerates:\n\n  WARNING: CPU: 30 PID: 938 at arch/x86/kvm/svm/nested.c:1877 svm_set_nested_state+0x34a/0x360 [kvm_amd]\n  Modules linked in: kvm_amd kvm irqbypass [last unloaded: kvm]\n  CPU: 30 UID: 1000 PID: 938 Comm: state_test Tainted: G        W           6.18.0-rc7-58e10b63777d-next-vm\n  Tainted: [W]=WARN\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n  RIP: 0010:svm_set_nested_state+0x34a/0x360 [kvm_amd]\n  Call Trace:\n   <TASK>\n   kvm_arch_vcpu_ioctl+0xf33/0x1700 [kvm]\n   kvm_vcpu_ioctl+0x4e6/0x8f0 [kvm]\n   __x64_sys_ioctl+0x8f/0xd0\n   do_syscall_64+0x61/0xad0\n   entry_SYSCALL_64_after_hwframe+0x4b/0x53\n\nSimply delete the WARN instead of trying to prevent userspace from shoving\n\"illegal\" state into CR3.  For better or worse, KVM's ABI allows userspace\nto set CPUID after SREGS, and vice versa, and KVM is very permissive when\nit comes to guest CPUID.  I.e. attempting to enforce the virtual CPU model\nwhen setting CPUID could break userspace.  Given that the WARN doesn't\nprovide any meaningful protection for KVM or benefit for userspace, simply\ndrop it even though the odds of breaking userspace are minuscule.\n\nOpportunistically delete a spurious newline."}],"providerMetadata":{"dateUpdated":"2026-05-11T22:22:10.929Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/155ec243ef726f4bc49536fa0bfb565dc011ab17"},{"url":"https://git.kernel.org/stable/c/580ea57840864d40e019bc13fd26afdc8d510a2f"},{"url":"https://git.kernel.org/stable/c/deb8f6dfd31d94b18dbeeaa8c01fbec5fc70fd2b"},{"url":"https://git.kernel.org/stable/c/ce904c8a5bbe697eae0f7e34b07095bd7a6dee19"},{"url":"https://git.kernel.org/stable/c/969e5e13ff5c18603f21d1f9f64ec9194e141ac0"},{"url":"https://git.kernel.org/stable/c/ebb2ab4f1c87d6b52776292cf7dc16aea48e95f8"},{"url":"https://git.kernel.org/stable/c/fc3ba56385d03501eb582e4b86691ba378e556f9"}],"title":"KVM: nSVM: Remove a user-triggerable WARN on nested_svm_load_cr3() succeeding","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-43315","datePublished":"2026-05-08T13:11:31.784Z","dateReserved":"2026-05-01T14:12:56.001Z","dateUpdated":"2026-05-11T22:22:10.929Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-05-08 14:16:39","lastModifiedDate":"2026-05-12 14:10:27","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"43315","Ordinal":"1","Title":"KVM: nSVM: Remove a user-triggerable WARN on nested_svm_load_cr3","CVE":"CVE-2026-43315","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"43315","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: nSVM: Remove a user-triggerable WARN on nested_svm_load_cr3() succeeding\n\nDrop the WARN in svm_set_nested_state() on nested_svm_load_cr3() failing\nas it is trivially easy to trigger from userspace by modifying CPUID after\nloading CR3.  E.g. modifying the state restoration selftest like so:\n\n  --- tools/testing/selftests/kvm/x86/state_test.c\n  +++ tools/testing/selftests/kvm/x86/state_test.c\n  @@ -280,7 +280,16 @@ int main(int argc, char *argv[])\n\n                 /* Restore state in a new VM.  */\n                  vcpu = vm_recreate_with_one_vcpu(vm);\n  -               vcpu_load_state(vcpu, state);\n  +\n  +               if (stage == 4) {\n  +                       state->sregs.cr3 = BIT(44);\n  +                       vcpu_load_state(vcpu, state);\n  +\n  +                       vcpu_set_cpuid_property(vcpu, X86_PROPERTY_MAX_PHY_ADDR, 36);\n  +                       __vcpu_nested_state_set(vcpu, &state->nested);\n  +               } else {\n  +                       vcpu_load_state(vcpu, state);\n  +               }\n\n                  /*\n                   * Restore XSAVE state in a dummy vCPU, first without doing\n\ngenerates:\n\n  WARNING: CPU: 30 PID: 938 at arch/x86/kvm/svm/nested.c:1877 svm_set_nested_state+0x34a/0x360 [kvm_amd]\n  Modules linked in: kvm_amd kvm irqbypass [last unloaded: kvm]\n  CPU: 30 UID: 1000 PID: 938 Comm: state_test Tainted: G        W           6.18.0-rc7-58e10b63777d-next-vm\n  Tainted: [W]=WARN\n  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015\n  RIP: 0010:svm_set_nested_state+0x34a/0x360 [kvm_amd]\n  Call Trace:\n   <TASK>\n   kvm_arch_vcpu_ioctl+0xf33/0x1700 [kvm]\n   kvm_vcpu_ioctl+0x4e6/0x8f0 [kvm]\n   __x64_sys_ioctl+0x8f/0xd0\n   do_syscall_64+0x61/0xad0\n   entry_SYSCALL_64_after_hwframe+0x4b/0x53\n\nSimply delete the WARN instead of trying to prevent userspace from shoving\n\"illegal\" state into CR3.  For better or worse, KVM's ABI allows userspace\nto set CPUID after SREGS, and vice versa, and KVM is very permissive when\nit comes to guest CPUID.  I.e. attempting to enforce the virtual CPU model\nwhen setting CPUID could break userspace.  Given that the WARN doesn't\nprovide any meaningful protection for KVM or benefit for userspace, simply\ndrop it even though the odds of breaking userspace are minuscule.\n\nOpportunistically delete a spurious newline.","Type":"Description","Title":"KVM: nSVM: Remove a user-triggerable WARN on nested_svm_load_cr3"}]}}}