{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-46036","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-05-13T15:03:33.093Z","datePublished":"2026-05-27T12:56:46.381Z","dateUpdated":"2026-08-05T12:29:15.525Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T12:29:15.525Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nvfio/cdx: Serialize VFIO_DEVICE_SET_IRQS with a per-device mutex\n\nvfio_cdx_set_msi_trigger() reads vdev->config_msi and operates on the\nvdev->cdx_irqs array based on its value, but provides no serialization\nagainst concurrent VFIO_DEVICE_SET_IRQS ioctls.  Two callers can race\nsuch that one observes config_msi as set while another clears it and\nfrees cdx_irqs via vfio_cdx_msi_disable(), resulting in a use-after-free\nof the cdx_irqs array.\n\nAdd a cdx_irqs_lock mutex to struct vfio_cdx_device and acquire it in\nvfio_cdx_set_msi_trigger(), which is the single chokepoint through\nwhich all updates to config_msi, cdx_irqs, and msi_count flow, covering\nboth the ioctl path and the close-device cleanup path.  This keeps the\ntest of config_msi atomic with the subsequent enable, disable, or\ntrigger operations.\n\nDrop the pre-call !cdx_irqs test from vfio_cdx_irqs_cleanup() as part\nof this change: the optimization it provided is redundant with the\n!config_msi early-return inside vfio_cdx_msi_disable(), and leaving the\ntest in place would be an unsynchronized read of state the new lock is\nmeant to protect."}],"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 bug is reached only via ioctl(VFIO_DEVICE_SET_IRQS) on a local /dev/vfio device file; there is no network or adjacent-network exposure.\nAC:L - This is an attacker-controlled race — the attacker issues concurrent enable/trigger and disable SET_IRQS ioctls from two threads on the same fd, controlling both sides, and the unserialized core dispatch lets them run in parallel and be hammered until won.\nPR:L - VFIO's threat model hands the device fd to unprivileged userspace (VM/passthrough processes), so an attacker only needs access to an already-bound vfio-cdx device fd, not init-namespace root; when uncertain, the higher-severity L is chosen.\nUI:N - Triggering the race requires only the attacker's own concurrent ioctls; no victim action is needed.\nS:U - The use-after-free corrupts the kernel's own cdx_irqs management array within the kernel security authority and does not cross an IOMMU/VM boundary.\nC:H - Use-after-free of a heap array whose freed contents are read back (including pointers) allows the attacker to reallocate the slab with controlled data and disclose kernel memory.\nI:H - The freed array's entries (a dereferenced/callable eventfd_ctx pointer and pointers passed to kfree/free_irq) enable heap-spray-based arbitrary write and control-flow hijacking.\nA:H - The use-after-free reliably causes kernel oops/panic when the freed cdx_irqs array is accessed."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/vfio/cdx/intr.c","drivers/vfio/cdx/main.c","drivers/vfio/cdx/private.h"],"versions":[{"version":"848e447e000c41894ff931dc7c004fd42c8840f8","lessThan":"ddf96e23c366c566283fce8377928851fa7f5e81","status":"affected","versionType":"git"},{"version":"848e447e000c41894ff931dc7c004fd42c8840f8","lessThan":"7b436ade16cc81095d79b79f8efa3af0a4f5c5a2","status":"affected","versionType":"git"},{"version":"848e447e000c41894ff931dc7c004fd42c8840f8","lessThan":"7530f34ec0ca1438d45a75dcb43183a1cc92eced","status":"affected","versionType":"git"},{"version":"848e447e000c41894ff931dc7c004fd42c8840f8","lessThan":"670e8864b1a218d72f08db40d0103adf38fa1d9b","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/vfio/cdx/intr.c","drivers/vfio/cdx/main.c","drivers/vfio/cdx/private.h"],"versions":[{"version":"6.10","status":"affected"},{"version":"0","lessThan":"6.10","status":"unaffected","versionType":"semver"},{"version":"6.12.86","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.27","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.0.4","lessThanOrEqual":"7.0.*","status":"unaffected","versionType":"semver"},{"version":"7.1","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":"6.10","versionEndExcluding":"6.12.86"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"6.18.27"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"7.0.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10","versionEndExcluding":"7.1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/ddf96e23c366c566283fce8377928851fa7f5e81"},{"url":"https://git.kernel.org/stable/c/7b436ade16cc81095d79b79f8efa3af0a4f5c5a2"},{"url":"https://git.kernel.org/stable/c/7530f34ec0ca1438d45a75dcb43183a1cc92eced"},{"url":"https://git.kernel.org/stable/c/670e8864b1a218d72f08db40d0103adf38fa1d9b"}],"title":"vfio/cdx: Serialize VFIO_DEVICE_SET_IRQS with a per-device mutex","x_generator":{"engine":"bippy-1.2.0"}}}}