In Zephyr's experimental USB host stack (CONFIGUSBHOSTSTACK), usbhdevicedisconnect() (subsys/usb/host/usbhdevice.c) freed the root usbdevice slab object without clearing the cached pointer ctx->root. The bus removal handler devremovedhandler() (subsys/usb/host/usbhcore.c) decides what to tear down solely from ctx->root, checking only that it is non-NULL.
Because UHC controller drivers (e.g. uhcmax3421e, uhcmcuxcommon) synthesize UHCEVTDEVREMOVED 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 usbhdevicedisconnect() with the dangling pointer, locking a mutex inside the freed object (use-after-free), removing the freed node from the device list, and calling kmemslab_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.
Impact 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 usbhdevicedisconnect() before freeing.
{
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/10xxx/CVE-2026-10663.json",
"cwe_ids": [
"CWE-416"
],
"unresolved_ranges": [
{
"extracted_events": [
{
"introduced": "4.4.0"
},
{
"fixed": "4.5.0"
}
],
"source": "AFFECTED_FIELD"
}
],
"cna_assigner": "zephyr"
}