{"affected":[{"defaultStatus":"unaffected","ecosystem":"https://github.com/zephyrproject-rtos/zephyr","packageName":"zephyr","product":"zephyr","source":"CNA: zephyr","vendor":"zephyrproject","versions":[{"lessThan":"4.4.2","status":"affected","version":"4.4.0","versionType":"semver"}]}],"cveId":"CVE-2026-10663","cwes":["CWE-416"],"description":"In Zephyr's experimental USB host stack (CONFIG_USB_HOST_STACK), usbh_device_disconnect() (subsys/usb/host/usbh_device.c) freed the root usb_device slab object without clearing the cached pointer ctx->root. The bus removal handler dev_removed_handler() (subsys/usb/host/usbh_core.c) decides what to tear down solely from ctx->root, checking only that it is non-NULL.\n\nBecause UHC controller drivers (e.g. uhc_max3421e, uhc_mcux_common) synthesize UHC_EVT_DEV_REMOVED directly from physical bus line state with no debounce or state guard, an attacker with physical USB access (or a rogue device that bounces its connection) can deliver a second device-removed event after a root device disconnect. The handler then re-enters usbh_device_disconnect() with the dangling pointer, locking a mutex inside the freed object (use-after-free), removing the freed node from the device list, and calling k_mem_slab_free() on the already-freed block (double-free). If the slab block has been reissued to a newly attached device in between, this corrupts a live object.\n\nImpact is denial of service (crash) and memory corruption; the attack vector is physical/local. The flaw was introduced in v4.4.0 by the connect/disconnect refactor and is fixed by clearing ctx->root in usbh_device_disconnect() before freeing.","epss":{"date":"2026-11-03","percentile":0.14745,"score":0.00236},"exploits":[],"kev":null,"metrics":[{"score":6.1,"severity":"medium","source":"CNA: zephyr","vector":"CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H","version":"3.1"}],"modifiedAt":1793768319854,"publishedAt":1783873008576,"references":[{"source":"CNA: zephyr","tags":["patch"],"url":"https://github.com/zephyrproject-rtos/zephyr/commit/4b87a8f161a44cb19505fa97db7cf72f64d49165"},{"source":"CNA: zephyr","tags":[],"url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-26q8-xjq3-f5p6"}],"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/4b87a8f161a44cb19505fa97db7cf72f64d49165"}],"revision":"0f09e193c4e13e28d4f27821b288b711bc854238fe8aa2dcbb40052f00015e2f","sources":[{"modifiedAt":1793768319854,"name":"CNA: zephyr","retrievedAt":1793768925257,"url":"https://www.cve.org/CVERecord?id=CVE-2026-10663"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1793768926158,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-10663"}],"ssvc":{"assessedAt":1783957617175,"automatable":"no","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"partial"},"status":"published","title":"Use-after-free / double-free of the root USB device in the experimental USB host stack","updatedAt":1793768926158}