{"id":"CVE-2026-72337","summary":"Bluetooth: 6lowpan: avoid untracked enable work","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: 6lowpan: avoid untracked enable work\n\nlowpan_enable_set() allocates a temporary work item and schedules\ndo_enable_set() on system_wq, then returns to debugfs. The debugfs active\noperation has ended at that point, but the worker still executes module\ntext and manipulates enable_6lowpan and listen_chan.\n\nbt_6lowpan_exit() removes the debugfs files and immediately closes and\nputs listen_chan. It has no pointer to the queued work item, so it cannot\ncancel or flush it before tearing down the state that the worker uses.\n\nThe buggy scenario involves two paths, with each column showing the order\nwithin that path:\n\ndebugfs enable write              module exit\n1. lowpan_enable_set() allocates  1. bt_6lowpan_exit() removes\n   set_enable work                   the debugfs file\n2. schedule_work() queues         2. bt_6lowpan_exit() closes\n   do_enable_set()                   and puts listen_chan\n3. the write operation returns    3. module teardown can continue\n4. do_enable_set() later runs\n   against stale state\n\nRun the enable state transition synchronously in lowpan_enable_set()\ninstead. The simple debugfs setter can sleep, and this file already handles\nthe 6LoWPAN control write synchronously under the same set_lock. Once the\nsetter returns, debugfs removal covers the whole operation and exit can no\nlonger race with an untracked work item.\n\nValidation reproduced this kernel report:\nBUG: KASAN: slab-use-after-free in do_enable_set+0x113/0x2e0\nWorkqueue: events do_enable_set [bluetooth_6lowpan]\nThe buggy address belongs to the object at ffff888109cb8000","modified":"2026-08-18T03:31:00.618220268Z","published":"2026-08-15T05:55:45.160Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72337.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/352a59dc1f4a41314b6f827c17e16af7ca88271a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/feb3fc2c38ed52003142f31e04109719b200c049"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/72xxx/CVE-2026-72337.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-72337"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"90305829635d90a5053ec99a261035b4ce0a2649"},{"fixed":"feb3fc2c38ed52003142f31e04109719b200c049"},{"fixed":"352a59dc1f4a41314b6f827c17e16af7ca88271a"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72337.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.19.0"},{"fixed":"7.1.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-72337.json"}}],"schema_version":"1.9.0"}