{"cve":"CVE-2026-64409","nvd":{"published":"2026-07-25T10:17:24.633","modified":"2026-09-04T15:27:06.223","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: btmtksdio: fix infinite loop in btmtksdio_txrx_work()\n\nEvery once in a while we see a hung btmtksdio_flush() task:\n\n INFO: task kworker/u17:0:189 blocked for more than 122 seconds.\n __cancel_work_timer+0x3f4/0x460\n cancel_work_sync+0x1c/0x2c\n btmtksdio_flush+0x2c/0x40\n hci_dev_open_sync+0x10c4/0x2190\n [..]\n\nIt all boils down to incorrect time_is_before_jiffies() usage in\nbtmtksdio_txrx_work().  The btmtksdio_txrx_work() loop is expected\nto be terminated if running for longer than 5*HZ.  However the\ntimeout check is twisted:  time_is_before_jiffies(old_jiffies + 5*HZ)\nevaluates to true when old_jiffies + 5*HZ is in the past i.e. when a\ntimeout has occurred.  Using OR with time_is_before_jiffies(txrx_timeout)\nmeans that:\n- before the 5-second timeout: the condition is `int_status || false`,\n  so it loops as long as there are pending interrupts.\n- after the 5-second timeout: the condition becomes `int_status || true`,\n  which is always true.\n\nWhen the loop becomes infinite btmtksdio_txrx_work() loop never\nterminates and never releases the SDIO host.\n\nFix loop termination condition to actually enforce a 5*HZ timeout.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-835"],"references":["https://git.kernel.org/stable/c/0039bdde36b23ccf1196635f1d52c5490481544d","https://git.kernel.org/stable/c/0f0a83e26a9c7fd4b243c315ce07161d2496d83d","https://git.kernel.org/stable/c/466540e045d01fcacf383a5beb8a2dad2fc53a26","https://git.kernel.org/stable/c/7b429d611060e87752e848851815537963726493","https://git.kernel.org/stable/c/a257407e2bbbb099ed427719a50563f67fa366d8"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:46:40.600842820+00:00"},"epss":{"cve":"CVE-2026-64409","score":0.00123,"percentile":0.01993,"date":"2026-10-31"},"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."]}