{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-39951", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-04-16T07:20:57.148Z", "datePublished": "2025-10-04T07:31:11.684Z", "dateUpdated": "2026-08-05T12:06:24.628Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:06:24.628Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\num: virtio_uml: Fix use-after-free after put_device in probe\n\nWhen register_virtio_device() fails in virtio_uml_probe(),\nthe code sets vu_dev->registered = 1 even though\nthe device was not successfully registered.\nThis can lead to use-after-free or other issues." } ], "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 code is a UML platform/virtio driver probe path reached through local device configuration (kernel command line, devicetree, mconsole, or sysfs driver bind), not through any remote protocol; the vhost-user peer is a local UNIX socket. No network-supplied data influences the failing call.\nAC:L - The `register_virtio_device()` failure can be produced deterministically via the OF path (`virtio_device_of_init()` returns -EINVAL when the parent node has more than one available child) and can also be induced by attacker-driven memory pressure on the `ida_alloc`/`dev_set_name`/`device_add` allocations; no condition outside the attacker's influence must hold.\nPR:L - A local unprivileged account on the UML instance suffices to drive the allocation-failure condition that makes the probe fail, and the resulting write-after-free happens with no further authorization check; no capability is validated in `virtio_uml_probe()` itself.\nUI:N - The faulty path executes automatically during driver probe/bind; nothing requires a victim to open a file, mount a filesystem, or otherwise interact.\nS:U - The corrupted memory and the vulnerable code are both in the kernel's own heap and security authority; there is no crossing of a VM, IOMMU, or sandbox boundary.\nC:H - The use-after-free leaves a freed `struct virtio_uml_device` (and a dangling `platform_set_drvdata` pointer) in play; an attacker who reclaims the slab slot with a chosen object gains a read primitive over kernel memory contents.\nI:H - The code performs an out-of-lifetime read-modify-write into the freed object, so heap grooming lets an attacker corrupt an unrelated reclaimed kernel structure, which is exploitable toward arbitrary write and control-flow hijack.\nA:H - Writing into freed slab memory corrupts allocator state and adjacent live objects, reliably producing kernel oops/panic (and KASAN slab-use-after-free splats) that take down the kernel instance." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "arch/um/drivers/virtio_uml.c" ], "versions": [ { "version": "04e5b1fb01834a602acaae2276b67a783a8c6159", "lessThan": "14c231959a16ca41bfdcaede72483362a8c645d7", "status": "affected", "versionType": "git" }, { "version": "04e5b1fb01834a602acaae2276b67a783a8c6159", "lessThan": "5e94e44c9cb30d7a383d8ac227f24a8c9326b770", "status": "affected", "versionType": "git" }, { "version": "04e5b1fb01834a602acaae2276b67a783a8c6159", "lessThan": "aaf900a83508c8cd5cdf765e7749f9076196ec7f", "status": "affected", "versionType": "git" }, { "version": "04e5b1fb01834a602acaae2276b67a783a8c6159", "lessThan": "4f364023ddcfe83f7073b973a9cb98584b7f2a46", "status": "affected", "versionType": "git" }, { "version": "04e5b1fb01834a602acaae2276b67a783a8c6159", "lessThan": "00e98b5a69034b251bb36dc6e7123d7648e218e4", "status": "affected", "versionType": "git" }, { "version": "04e5b1fb01834a602acaae2276b67a783a8c6159", "lessThan": "c2ff91255e0157b356cff115d8dc3eeb5162edf2", "status": "affected", "versionType": "git" }, { "version": "04e5b1fb01834a602acaae2276b67a783a8c6159", "lessThan": "7ebf70cf181651fe3f2e44e95e7e5073d594c9c0", "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/um/drivers/virtio_uml.c" ], "versions": [ { "version": "5.5", "status": "affected" }, { "version": "0", "lessThan": "5.5", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.245", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.194", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.154", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.108", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.49", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.16.9", "lessThanOrEqual": "6.16.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.17", "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": "5.5", "versionEndExcluding": "5.10.245" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "5.15.194" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "6.1.154" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "6.6.108" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "6.12.49" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "6.16.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.5", "versionEndExcluding": "6.17" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/14c231959a16ca41bfdcaede72483362a8c645d7" }, { "url": "https://git.kernel.org/stable/c/5e94e44c9cb30d7a383d8ac227f24a8c9326b770" }, { "url": "https://git.kernel.org/stable/c/aaf900a83508c8cd5cdf765e7749f9076196ec7f" }, { "url": "https://git.kernel.org/stable/c/4f364023ddcfe83f7073b973a9cb98584b7f2a46" }, { "url": "https://git.kernel.org/stable/c/00e98b5a69034b251bb36dc6e7123d7648e218e4" }, { "url": "https://git.kernel.org/stable/c/c2ff91255e0157b356cff115d8dc3eeb5162edf2" }, { "url": "https://git.kernel.org/stable/c/7ebf70cf181651fe3f2e44e95e7e5073d594c9c0" } ], "title": "um: virtio_uml: Fix use-after-free after put_device in probe", "x_generator": { "engine": "bippy-1.2.0" } } } }