{"affected":[{"defaultStatus":"unaffected","ecosystem":"https://github.com/zephyrproject-rtos/zephyr","packageName":"zephyr","product":"zephyr","source":"CNA: zephyr","vendor":"zephyrproject","versions":[{"lessThan":"4.6.0","status":"affected","version":"1.14.0","versionType":"semver"}]}],"cpeConfigurations":[{"negate":false,"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:zephyrproject:zephyr:*:*:*:*:*:*:*:*","versionEndIncluding":"4.4.1","versionStartIncluding":"1.14.0","vulnerable":true}],"negate":false,"operator":"OR"}],"operator":"OR"}],"cveId":"CVE-2026-10667","cwes":["CWE-416"],"description":"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.","epss":{"date":"2026-11-03","percentile":0.04127,"score":0.00149},"exploits":[{"kind":"exploit","source":"ADP: CISA-ADP","url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-9x5j-h3rh-x579"},{"kind":"exploit","source":"vulnerabilities@zephyrproject.org","url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-9x5j-h3rh-x579"},{"kind":"exploit","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-9x5j-h3rh-x579"}],"kev":null,"metrics":[{"score":7.8,"severity":"high","source":"CNA: zephyr","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H","version":"3.1"},{"score":7.8,"severity":"high","source":"NVD: vulnerabilities@zephyrproject.org","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H","version":"3.1"}],"modifiedAt":1793769505287,"publishedAt":1783873010693,"references":[{"source":"CNA: zephyr","tags":["patch"],"url":"https://github.com/zephyrproject-rtos/zephyr/commit/fdc42fa256b8c2a7b27790f032d5385f8058c4a9"},{"source":"CNA: zephyr","tags":[],"url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-9x5j-h3rh-x579"},{"source":"ADP: CISA-ADP","tags":["exploit"],"url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-9x5j-h3rh-x579"},{"source":"vulnerabilities@zephyrproject.org","tags":["Patch"],"url":"https://github.com/zephyrproject-rtos/zephyr/commit/fdc42fa256b8c2a7b27790f032d5385f8058c4a9"},{"source":"vulnerabilities@zephyrproject.org","tags":["Exploit","Patch","Vendor Advisory"],"url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-9x5j-h3rh-x579"},{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","tags":["Exploit","Patch","Vendor Advisory"],"url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-9x5j-h3rh-x579"}],"remediation":[{"kind":"fix","source":"CNA: zephyr","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/zephyrproject-rtos/zephyr/commit/fdc42fa256b8c2a7b27790f032d5385f8058c4a9"},{"kind":"fix","source":"vulnerabilities@zephyrproject.org","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/zephyrproject-rtos/zephyr/commit/fdc42fa256b8c2a7b27790f032d5385f8058c4a9"},{"kind":"fix","source":"vulnerabilities@zephyrproject.org","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-9x5j-h3rh-x579"},{"kind":"fix","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-9x5j-h3rh-x579"}],"revision":"df85735bdd0efed14ba87c770ff2ced3d0d502138056a6b5c575f4135344ce1b","sources":[{"modifiedAt":1793768324893,"name":"CNA: zephyr","retrievedAt":1793768929763,"url":"https://www.cve.org/CVERecord?id=CVE-2026-10667"},{"modifiedAt":1793769505287,"name":"NVD","retrievedAt":1793772950355,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-10667"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1793768961752,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-10667"}],"ssvc":{"assessedAt":1783957781562,"automatable":"no","exploitation":"poc","source":"ADP: CISA-ADP","technicalImpact":"total"},"status":"published","title":"SMP use-after-free in Zephyr `CONFIG_USERSPACE` dynamic kernel-object tracking, reachable from unprivileged user threads","updatedAt":1793772950355}