{"id":"CVE-2026-97996","revision":"a8512f2af91c4b8b8c9d836763a89f1e","records":[{"revision":"a8512f2af91c4b8b8c9d836763a89f1e","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-97996","aliases":[],"title":"virtio: fix use-after-free in unregister_virtio_device()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nvirtio: fix use-after-free in unregister_virtio_device()\n\ndevice_unregister() is device_del() plus put_device(). When the caller\nholds no extra reference, that drops the last one and runs the release\ncallback, which for several transports frees the memory the embedded\nstruct virtio_device sits in. unregister_virtio_device() then calls\nvirtio_debug_device_exit(), which reads dev->debugfs_dir out of the freed\nobject.\n\nAffected transports are the ones whose release callback frees and whose\nremove path takes no reference: virtio_mmio, virtio_vdpa, virtio_uml,\nmlxbf-tmfifo and virtio_ccw. virtio_pci is unaffected because\nvirtio_pci_remove() brackets the call with get_device() and put_device().\n\nRemove the debugfs entries before the device can go away. They are only\naccessed through the protected debugfs interface, so\ndebugfs_remove_recursive() waits for in-progress file operations before\nreturning. Tearing them down while the device is still alive is therefore\nsafe.\n\nReproduced on User-Mode Linux with CONFIG_KASAN and CONFIG_VIRTIO_DEBUG\nby unbinding a virtio-uml device:\n\n  BUG: KASAN: slab-use-after-free in virtio_debug_device_exit+0x36/0x4d\n  Read of size 8 at addr 00000000616e0b10 by task init/1\n   __asan_report_load8_noabort\n   virtio_debug_device_exit+0x36/0x4d\n   unregister_virtio_device+0x48/0x75\n   virtio_uml_remove\n   platform_remove\n   device_release_driver_internal\n   unbind_store\n\n  Freed by task 1:\n   kfree\n   virtio_uml_release_dev\n   device_release\n   kobject_put\n   put_device\n   device_unregister\n\nWith this applied, the report is gone and unbind is clean.","state":0,"publishedAt":"2026-09-25T10:23:26.913+00:00","modifiedAt":"2026-10-19T09:12:03.153+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"drivers/virtio/virtio.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"96a8326d69fffd7e8c2eb737dc060d8009a33b39\",\n                            \"lessThan\": \"951cad50cba89e736afdee4a730e0e52f9245c9b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"96a8326d69fffd7e8c2eb737dc060d8009a33b39\",\n                            \"lessThan\": \"77dbd10a701a30fdfea5c3bb7a29163128f9a9c7\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"96a8326d69fffd7e8c2eb737dc060d8009a33b39\",\n                            \"lessThan\": \"caf042153016d651b55d0fb4a63cdf7d0d23dee2\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"96a8326d69fffd7e8c2eb737dc060d8009a33b39\",\n                            \"lessThan\": \"3f9a0fceb730f5107d52421ead5568eae25a0049\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"drivers/virtio/virtio.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.10\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"6.10\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.111\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.53\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.7\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/951cad50cba89e736afdee4a730e0e52f9245c9b","https://git.kernel.org/stable/c/77dbd10a701a30fdfea5c3bb7a29163128f9a9c7","https://git.kernel.org/stable/c/caf042153016d651b55d0fb4a63cdf7d0d23dee2","https://git.kernel.org/stable/c/3f9a0fceb730f5107d52421ead5568eae25a0049"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-97996","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-97996","identifiers":["CVE-2026-97996"]},"retained":false,"historicalAffected":[]}],"coverage":[]}