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    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-10667",
        "assignerOrgId": "e2e69745-5e70-4e92-8431-deb5529a81ad",
        "state": "PUBLISHED",
        "assignerShortName": "zephyr",
        "dateReserved": "2026-06-02T15:25:29.239Z",
        "datePublished": "2026-07-12T16:16:50.693Z",
        "dateUpdated": "2026-07-14T18:38:45.767Z"
    },
    "containers": {
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            "providerMetadata": {
                "orgId": "e2e69745-5e70-4e92-8431-deb5529a81ad",
                "shortName": "zephyr",
                "dateUpdated": "2026-07-14T18:38:45.767Z"
            },
            "title": "SMP use-after-free in Zephyr `CONFIG_USERSPACE` dynamic kernel-object tracking, reachable from unprivileged user threads",
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Zephyr's dynamic kernel-object tracking (kernel/userspace/userspace.c, formerly kernel/userspace.c) maintains a doubly-linked list (obj_list) of dynamically allocated kernel objects. Iteration over this list in k_object_wordlist_foreach() was performed under lists_lock using the SAFE iterator (which caches the next node), but list removal and freeing of nodes was performed under different, disjoint spinlocks: objfree_lock in k_object_free() and obj_lock in unref_check(). On an SMP system, while one CPU iterated obj_list under lists_lock, another CPU could unlink and k_free() the dyn_obj node that the iterator had cached as its next pointer, causing the iterator to dereference freed kernel memory (use-after-free / dangling list traversal). All of the racing operations are reachable from unprivileged user-mode threads via system calls: k_object_alloc/k_object_alloc_size and k_object_release drive removals through unref_check() (under obj_lock), while k_thread_abort and thread creation drive the iteration through k_thread_perms_all_clear()/k_thread_perms_inherit() (under lists_lock). A deprivileged user thread on a CONFIG_SMP + CONFIG_USERSPACE build can therefore corrupt the kernel's object-tracking structures across the userspace security boundary, yielding kernel memory corruption (potential privilege escalation) or a kernel crash (denial of service). The fix removes objfree_lock and serializes every obj_list modification under lists_lock, including holding it across find+remove in k_object_free() and around unref_check() in k_thread_perms_clear(). Affects CONFIG_SMP+CONFIG_USERSPACE+CONFIG_DYNAMIC_OBJECTS configurations; the defect dates to the 2019 spinlockification (commit 8a3d57b6cc6, first released in v1.14.0) and shipped through v4.4.0."
                }
            ],
            "affected": [
                {
                    "vendor": "zephyrproject",
                    "product": "zephyr",
                    "collectionURL": "https://github.com/zephyrproject-rtos/zephyr",
                    "packageName": "zephyr",
                    "defaultStatus": "unaffected",
                    "programFiles": [
                        "kernel/userspace/userspace.c"
                    ],
                    "versions": [
                        {
                            "version": "1.14.0",
                            "status": "affected",
                            "lessThan": "4.5.0",
                            "versionType": "semver"
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://github.com/zephyrproject-rtos/zephyr/commit/fdc42fa256b8c2a7b27790f032d5385f8058c4a9",
                    "name": "Fix commit",
                    "tags": [
                        "patch"
                    ]
                },
                {
                    "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-9x5j-h3rh-x579",
                    "name": "GHSA-9x5j-h3rh-x579"
                }
            ],
            "metrics": [
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                    "format": "CVSS",
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
                        "baseScore": 7.8,
                        "baseSeverity": "HIGH"
                    }
                }
            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "description": "use-after-free",
                            "cweId": "CWE-416",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "x_generator": {
                "engine": "cvelib 1.8.0"
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        "adp": [
            {
                "references": [
                    {
                        "url": "https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-9x5j-h3rh-x579",
                        "tags": [
                            "exploit"
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                ],
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-07-13T15:49:41.562734Z",
                                "id": "CVE-2026-10667",
                                "options": [
                                    {
                                        "Exploitation": "poc"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "total"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
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                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
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                    "dateUpdated": "2026-07-13T15:50:03.686Z"
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