{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-89913","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-09-11T19:38:34.774Z","datePublished":"2026-09-16T10:32:09.947Z","dateUpdated":"2026-09-17T09:29:16.550Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-17T09:29:16.550Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: arm64: vgic-v3: take an LPI reference in vgic_v3_save_pending_tables\n\nvgic_v3_save_pending_tables() iterates dist->lpi_xa using xa_for_each()\nand dereferences the returned struct vgic_irq in the loop body without\nholding a reference on the LPI.\n\nThe xarray iterator only provides temporary RCU coverage while looking up\nthe current entry. That is not sufficient for this loop body, which reads\nfields from struct vgic_irq and performs guest memory accesses before the\niteration completes.\n\nA concurrent path can trigger this race: the irqfd cached injection path\n(vgic_its_inject_cached_translation) obtains a transient LPI reference\nvia vgic_its_check_cache() without holding kvm->lock, vcpu->mutex,\nconfig_lock, or its_lock. If guest ITS DISCARD then drops the cache and\nITE references under its_lock, the transient inject reference may become\nthe final one. When vgic_put_irq() drops it, the LPI is erased from\nlpi_xa and freed via kfree_rcu(). Meanwhile, vgic_v3_save_pending_tables()\nmay still hold a stale pointer obtained from the xarray iterator and\ndereference it after the RCU grace period completes.\n\nFix this by re-fetching each iterated LPI via vgic_get_irq(), which takes\na stable reference, and dropping it with vgic_put_irq() on all paths.\nThis matches the pattern already used by other lpi_xa iterators in the\nvgic ITS code."}],"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 UAF is reached only via local KVM: KVM_SET_DEVICE_ATTR(KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES) on the VGIC device fd, irqfd/KVM_SIGNAL_MSI cached injection, and guest GICv3 ITS MMIO writes to GITS_CWRITER (DISCARD); there is no network, adjacent, or physical path.\nAC:L - A kvm-group attacker who owns the VMM controls every side of the race (irqfd/KVM_SIGNAL_MSI cached inject, guest ITS DISCARD, and SAVE_PENDING_TABLES). The save path sleeps in kvm_read_guest_lock() so the kfree_rcu() window is attacker-driven rather than an uninfluenced host condition.\nPR:L - Creating a VM and issuing VGIC device attributes requires only /dev/kvm access (typically 0660 kvm group) or tenancy in an arm64 KVM guest; kvm_dev_ioctl_create_vm() and kvm_device_ioctl() have no capable() gate, so init-namespace root is not required.\nUI:N - The attacker issues the VGIC save ioctl, irqfd/MSI injection, and guest ITS DISCARD themselves; no separate victim action such as mounting a filesystem or opening a crafted file is required.\nS:C - Use-after-free of host-kernel struct vgic_irq in KVM's VGIC ITS LPI xarray crosses the guest-to-host hypervisor boundary; corrupting host LPI objects from a VM/VMM can escape the guest security authority.\nC:H - This is a host-kernel use-after-free of struct vgic_irq after kfree_rcu(); reclaiming the freed object lets the save loop read attacker-controlled irq fields (target_vcpu, intid, pending_latch), yielding an arbitrary host kernel read primitive.\nI:H - Host heap UAF of vgic_irq with attacker-controlled irqfd/DISCARD timing enables heap spray of fake irq objects, providing write and control-flow hijack primitives against the host kernel.\nA:H - Dereferencing the freed vgic_irq after the RCU grace period (the save path sleeps in kvm_read_guest_lock()) causes a host kernel oops or panic even without a full exploit."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/arm64/kvm/vgic/vgic-v3.c"],"versions":[{"version":"280771252c1bae0947215c59fb9ea6a8d9f8399d","lessThan":"7631f95297560157d3a9283cb999e3be00103348","status":"affected","versionType":"git"},{"version":"280771252c1bae0947215c59fb9ea6a8d9f8399d","lessThan":"d3a2d20b7248ea67465af1cf79c79f90ff70926c","status":"affected","versionType":"git"},{"version":"280771252c1bae0947215c59fb9ea6a8d9f8399d","lessThan":"f5b8f203bfc07a5a257dff859e66d2c500f9f509","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/arm64/kvm/vgic/vgic-v3.c"],"versions":[{"version":"4.12","status":"affected"},{"version":"0","lessThan":"4.12","status":"unaffected","versionType":"semver"},{"version":"6.18.51","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.2.5","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3-rc1","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":"4.12","versionEndExcluding":"6.18.51"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"7.2.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"7.3-rc1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/7631f95297560157d3a9283cb999e3be00103348"},{"url":"https://git.kernel.org/stable/c/d3a2d20b7248ea67465af1cf79c79f90ff70926c"},{"url":"https://git.kernel.org/stable/c/f5b8f203bfc07a5a257dff859e66d2c500f9f509"}],"title":"KVM: arm64: vgic-v3: take an LPI reference in vgic_v3_save_pending_tables","x_generator":{"engine":"bippy-1.2.0"}}}}