{"id":"CVE-2026-43214","state":"PUBLISHED","title":"KVM: x86: Add SRCU protection for reading PDPTRs in __get_sregs2()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86: Add SRCU protection for reading PDPTRs in __get_sregs2()\n\nAdd SRCU read-side protection when reading PDPTR registers in\n__get_sregs2().\n\nReading PDPTRs may trigger access to guest memory:\nkvm_pdptr_read() -> svm_cache_reg() -> load_pdptrs() ->\nkvm_vcpu_read_guest_page() -> kvm_vcpu_gfn_to_memslot()\n\nkvm_vcpu_gfn_to_memslot() dereferences memslots via __kvm_memslots(),\nwhich uses srcu_dereference_check() and requires either kvm->srcu or\nkvm->slots_lock to be held. Currently only vcpu->mutex is held,\ntriggering lockdep warning:\n\n=============================\nWARNING: suspicious RCU usage in kvm_vcpu_gfn_to_memslot\n6.12.59+ #3 Not tainted\n\ninclude/linux/kvm_host.h:1062 suspicious rcu_dereference_check() usage!\n\nother info that might help us debug this:\n\nrcu_scheduler_active = 2, debug_locks = 1\n1 lock held by syz.5.1717/15100:\n #0: ff1100002f4b00b0 (&vcpu->mutex){+.+.}-{3:3}, at: kvm_vcpu_ioctl+0x1d5/0x1590\n\nCall Trace:\n <TASK>\n __dump_stack lib/dump_stack.c:94 [inline]\n dump_stack_lvl+0xf0/0x120 lib/dump_stack.c:120\n lockdep_rcu_suspicious+0x1e3/0x270 kernel/locking/lockdep.c:6824\n __kvm_memslots include/linux/kvm_host.h:1062 [inline]\n __kvm_memslots include/linux/kvm_host.h:1059 [inline]\n kvm_vcpu_memslots include/linux/kvm_host.h:1076 [inline]\n kvm_vcpu_gfn_to_memslot+0x518/0x5e0 virt/kvm/kvm_main.c:2617\n kvm_vcpu_read_guest_page+0x27/0x50 virt/kvm/kvm_main.c:3302\n load_pdptrs+0xff/0x4b0 arch/x86/kvm/x86.c:1065\n svm_cache_reg+0x1c9/0x230 arch/x86/kvm/svm/svm.c:1688\n kvm_pdptr_read arch/x86/kvm/kvm_cache_regs.h:141 [inline]\n __get_sregs2 arch/x86/kvm/x86.c:11784 [inline]\n kvm_arch_vcpu_ioctl+0x3e20/0x4aa0 arch/x86/kvm/x86.c:6279\n kvm_vcpu_ioctl+0x856/0x1590 virt/kvm/kvm_main.c:4663\n vfs_ioctl fs/ioctl.c:51 [inline]\n __do_sys_ioctl fs/ioctl.c:907 [inline]\n __se_sys_ioctl fs/ioctl.c:893 [inline]\n __x64_sys_ioctl+0x18b/0x210 fs/ioctl.c:893\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0xbd/0x1d0 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nFound by Linux Verification Center (linuxtesting.org) with Syzkaller.","publishedAt":"2026-05-06T11:28:16.766Z","updatedAt":"2026-10-19T19:16:24.580Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"6dba940352038b56db9b591b172fb2ec76a5fd5e","status":"affected","lessThan":"f621ca24f9f489e226e22560761b04884984133b","versionType":"git"},{"version":"6dba940352038b56db9b591b172fb2ec76a5fd5e","status":"affected","lessThan":"708e20c66b2761d878a2bc3c7534e7f814e4dec5","versionType":"git"},{"version":"6dba940352038b56db9b591b172fb2ec76a5fd5e","status":"affected","lessThan":"9f2bfea51151dfbb24b52f452eb3d5f5fe0e506e","versionType":"git"},{"version":"6dba940352038b56db9b591b172fb2ec76a5fd5e","status":"affected","lessThan":"57536ff0a6bd69a5808d682925202babdb5ddc13","versionType":"git"},{"version":"6dba940352038b56db9b591b172fb2ec76a5fd5e","status":"affected","lessThan":"b33f8d816950b10e7879cd8ffd7ae4b649ada4db","versionType":"git"},{"version":"6dba940352038b56db9b591b172fb2ec76a5fd5e","status":"affected","lessThan":"95d848dc7e639988dbb385a8cba9b484607cf98c","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/kvm/x86.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.14","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.14","versionType":"semver"},{"version":"6.1.165","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.128","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.75","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.16","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.6","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/kvm/x86.c"]}],"references":["https://git.kernel.org/stable/c/f621ca24f9f489e226e22560761b04884984133b","https://git.kernel.org/stable/c/708e20c66b2761d878a2bc3c7534e7f814e4dec5","https://git.kernel.org/stable/c/9f2bfea51151dfbb24b52f452eb3d5f5fe0e506e","https://git.kernel.org/stable/c/57536ff0a6bd69a5808d682925202babdb5ddc13","https://git.kernel.org/stable/c/b33f8d816950b10e7879cd8ffd7ae4b649ada4db","https://git.kernel.org/stable/c/95d848dc7e639988dbb385a8cba9b484607cf98c"],"weaknesses":["CWE-362"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/43xxx/CVE-2026-43214.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-43214","state":"PUBLISHED","datePublished":"2026-05-06T11:28:16.766Z","dateUpdated":"2026-10-19T19:16:24.580Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-05-01T14:12:55.993Z"},"containers":{"cna":{"title":"KVM: x86: Add SRCU protection for reading PDPTRs in __get_sregs2()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86: Add SRCU protection for reading PDPTRs in __get_sregs2()\n\nAdd SRCU read-side protection when reading PDPTR registers in\n__get_sregs2().\n\nReading PDPTRs may trigger access to guest memory:\nkvm_pdptr_read() -> svm_cache_reg() -> load_pdptrs() ->\nkvm_vcpu_read_guest_page() -> kvm_vcpu_gfn_to_memslot()\n\nkvm_vcpu_gfn_to_memslot() dereferences memslots via __kvm_memslots(),\nwhich uses srcu_dereference_check() and requires either kvm->srcu or\nkvm->slots_lock to be held. Currently only vcpu->mutex is held,\ntriggering lockdep warning:\n\n=============================\nWARNING: suspicious RCU usage in kvm_vcpu_gfn_to_memslot\n6.12.59+ #3 Not tainted\n\ninclude/linux/kvm_host.h:1062 suspicious rcu_dereference_check() usage!\n\nother info that might help us debug this:\n\nrcu_scheduler_active = 2, debug_locks = 1\n1 lock held by syz.5.1717/15100:\n #0: ff1100002f4b00b0 (&vcpu->mutex){+.+.}-{3:3}, at: kvm_vcpu_ioctl+0x1d5/0x1590\n\nCall Trace:\n <TASK>\n __dump_stack lib/dump_stack.c:94 [inline]\n dump_stack_lvl+0xf0/0x120 lib/dump_stack.c:120\n lockdep_rcu_suspicious+0x1e3/0x270 kernel/locking/lockdep.c:6824\n __kvm_memslots include/linux/kvm_host.h:1062 [inline]\n __kvm_memslots include/linux/kvm_host.h:1059 [inline]\n kvm_vcpu_memslots include/linux/kvm_host.h:1076 [inline]\n kvm_vcpu_gfn_to_memslot+0x518/0x5e0 virt/kvm/kvm_main.c:2617\n kvm_vcpu_read_guest_page+0x27/0x50 virt/kvm/kvm_main.c:3302\n load_pdptrs+0xff/0x4b0 arch/x86/kvm/x86.c:1065\n svm_cache_reg+0x1c9/0x230 arch/x86/kvm/svm/svm.c:1688\n kvm_pdptr_read arch/x86/kvm/kvm_cache_regs.h:141 [inline]\n __get_sregs2 arch/x86/kvm/x86.c:11784 [inline]\n kvm_arch_vcpu_ioctl+0x3e20/0x4aa0 arch/x86/kvm/x86.c:6279\n kvm_vcpu_ioctl+0x856/0x1590 virt/kvm/kvm_main.c:4663\n vfs_ioctl fs/ioctl.c:51 [inline]\n __do_sys_ioctl fs/ioctl.c:907 [inline]\n __se_sys_ioctl fs/ioctl.c:893 [inline]\n __x64_sys_ioctl+0x18b/0x210 fs/ioctl.c:893\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0xbd/0x1d0 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nFound by Linux Verification Center (linuxtesting.org) with Syzkaller."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"6dba940352038b56db9b591b172fb2ec76a5fd5e","status":"affected","lessThan":"f621ca24f9f489e226e22560761b04884984133b","versionType":"git"},{"version":"6dba940352038b56db9b591b172fb2ec76a5fd5e","status":"affected","lessThan":"708e20c66b2761d878a2bc3c7534e7f814e4dec5","versionType":"git"},{"version":"6dba940352038b56db9b591b172fb2ec76a5fd5e","status":"affected","lessThan":"9f2bfea51151dfbb24b52f452eb3d5f5fe0e506e","versionType":"git"},{"version":"6dba940352038b56db9b591b172fb2ec76a5fd5e","status":"affected","lessThan":"57536ff0a6bd69a5808d682925202babdb5ddc13","versionType":"git"},{"version":"6dba940352038b56db9b591b172fb2ec76a5fd5e","status":"affected","lessThan":"b33f8d816950b10e7879cd8ffd7ae4b649ada4db","versionType":"git"},{"version":"6dba940352038b56db9b591b172fb2ec76a5fd5e","status":"affected","lessThan":"95d848dc7e639988dbb385a8cba9b484607cf98c","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/kvm/x86.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.14","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.14","versionType":"semver"},{"version":"6.1.165","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.128","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.75","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.16","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.6","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/kvm/x86.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/f621ca24f9f489e226e22560761b04884984133b"},{"url":"https://git.kernel.org/stable/c/708e20c66b2761d878a2bc3c7534e7f814e4dec5"},{"url":"https://git.kernel.org/stable/c/9f2bfea51151dfbb24b52f452eb3d5f5fe0e506e"},{"url":"https://git.kernel.org/stable/c/57536ff0a6bd69a5808d682925202babdb5ddc13"},{"url":"https://git.kernel.org/stable/c/b33f8d816950b10e7879cd8ffd7ae4b649ada4db"},{"url":"https://git.kernel.org/stable/c/95d848dc7e639988dbb385a8cba9b484607cf98c"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerable path is reached through local KVM ioctls on `/dev/kvm`, specifically creating a VM/vCPU and issuing `KVM_GET_SREGS2` on the vCPU fd. It is not reachable directly from network, adjacent, or physical input.\nAC:L - The attacker can control both sides of the race by issuing `KVM_GET_SREGS2` concurrently with memslot updates such as `KVM_SET_USER_MEMORY_REGION`. The needed PAE/SVM/NPT state is attacker-configurable in a reasonable KVM deployment.\nPR:L - Exploitation requires local access to KVM device fds, but the kernel path has no CAP_SYS_ADMIN-style check once `/dev/kvm` is accessible. This is low privilege rather than high privilege.\nUI:N - No victim action is required after the attacker has local KVM access. The attacker can create the VM, configure vCPU state, and trigger the racing ioctls directly.\nS:U - This is a host userspace-to-host kernel KVM ioctl vulnerability, not a guest-to-host escape path. The impacted kernel resources are within the same security scope.\nC:H - The missing SRCU protection can allow memslot metadata to be accessed after concurrent replacement or freeing. As a KVM memslot use-after-free condition, the higher defensible confidentiality impact is high.\nI:H - The same UAF-style race can allow attacker-shaped heap reuse of KVM metadata and corruption of KVM/kernel execution state. Following the required higher-severity rule for UAF memory corruption, integrity impact is high.\nA:H - At minimum, racing an unprotected memslot dereference can trigger kernel warnings, invalid pointer dereferences, or crashes. Kernel crash or oops impact is high availability."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:26:39.670Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"6.1.165"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"6.6.128"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"6.12.75"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"6.18.16"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"6.19.6"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.14","versionEndExcluding":"7.0"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-43214","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:15:51.096773Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-362","lang":"en","type":"CWE","description":"CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T19:16:24.580Z"}}]}}}