{"cve":"CVE-2026-72073","nvd":{"published":"2026-08-15T06:21:17.123","modified":"2026-10-21T13:19:32.510","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmmc: vub300: fix use-after-free on probe failure\n\nThe vub300 driver lifetime-manages its controller state using\nvub300->kref, with vub300_delete() freeing the mmc host when the last\nreference is dropped. The probe error path after the inactivity timer has\nbeen armed still bypasses that lifetime rule, however, and falls through\nto mmc_free_host() directly if mmc_add_host() fails.\n\nThe race window is between arming the inactivity timer and reaching the\nprobe error unwind after mmc_add_host() fails:\n\n        probe thread                     timer/workqueue\n        ------------                     ---------------\n        kref_init(&vub300->kref)         ref = 1\n        kref_get(&vub300->kref)          ref = 2, timer ref\n        add_timer(inactivity_timer)      fires after one second\n        |\n        |   race window\n        |<---------------------------------------------------->\n        |\n        mmc_add_host(mmc)\n                                         inactivity timer fires\n                                         vub300_queue_dead_work()\n                                           kref_get()          ref = 3\n                                           queue_work(deadwork)\n        mmc_add_host() fails\n        timer_delete_sync()\n        mmc_free_host(mmc)\n          frees vub300\n                                         deadwork runs\n                                           use-after-free\n\nThe inactivity timeout is one second, so this would require\nmmc_add_host() to both fail and take more than one second to do so. This\nis unlikely to happen in practice, but the error path is still wrong.\n\ntimer_delete_sync() only waits for the timer callback itself. It does\nnot flush deadwork that the callback may already have queued. As a\nresult, queued deadwork can still hold a kref while the probe error path\ndirectly frees the backing mmc host, including the vub300 storage.\n\nFix this by using the same lifetime mechanism as disconnect. Clear\nvub300->interface so that the timer callback and any queued deadwork\nreturn early and drop their references, then drop the initial probe\nreference and return without falling through to err_free_host.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/5b82af744e06cd741938c3da54fdbe564a7e52d9","https://git.kernel.org/stable/c/618cf6b139503ec18ef93ffd663396aaf99b763a","https://git.kernel.org/stable/c/6c66653dac9b25272d5fd4ed42a34aa5249e16df","https://git.kernel.org/stable/c/a3b5f242997a3be7404112fd48784881560aea57","https://git.kernel.org/stable/c/face65f80c6946c631ca3490b4ebd2c016a4fd2c"],"products":[],"source":"nvd","synced_at":"2026-10-22T16:41:11.231219466+00:00"},"epss":{"cve":"CVE-2026-72073","score":0.00219,"percentile":0.12319,"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."]}