{"cve":"CVE-2026-99024","nvd":{"published":"2026-10-23T13:17:25.357","modified":"2026-10-23T13:17:25.357","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\noptee: register TEE devices only once fully initialized\n\noptee_probe() called tee_device_register() on both the client and the\nsupplicant device before the rest of struct optee had been initialized.\n\ntee_device_register() calls cdev_device_add(), which does two things at\nonce: it creates /dev/tee0 and /dev/teepriv0, and it links the device\ninto the tee class so that class_find_device() can find it. From that\nmoment on the device is reachable both from user space via tee_open()\nand from kernel space via tee_client_open_context(). The only gate in\nteedev_open() is tee_device_get(), which merely checks that\nteedev->desc is non-NULL, which was already set by tee_device_alloc().\nTherefore, there is effectively no gate at all.\n\nA context opened in that window can run against a struct optee where\n\n  - optee->call_queue.mutex is not initialized by optee_cq_init()\n  - optee->supp mutex and completions is not initialized by\n    optee_supp_init()\n  - optee->rpmb_dev_mutex is not initialized yet,\n  - the message argument cache is not initialized by\n    optee_shm_arg_cache_init()\n  - optee->ctx is still NULL\n\nAny open session or invoke during this window takes uninitialized\nmutexes and dereferences a NULL pointer.\n\nFix it by moving both tee_device_register() calls down to the point\nwhere all of struct optee is set up.\n\n[JW: adding fixes and cc]","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/262062c01f5a817104c88bf6eacb7c6ffdc7018d","https://git.kernel.org/stable/c/2f7240f0a6fd83df274fc0a2abf0609b4e6bd388","https://git.kernel.org/stable/c/681adbc9c7a820279582a295e183fa6a1d1b4ec4","https://git.kernel.org/stable/c/8cae1605be8a047ae3a62df07b9474d61462c4f6","https://git.kernel.org/stable/c/c108feca0a096f8db25d1b69130035025e9e936d"],"products":[],"source":"nvd","synced_at":"2026-10-23T16:39:28.036610720+00:00"},"epss":{"cve":"CVE-2026-99024","score":0.00168,"percentile":0.0616,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}