{"id":"CVE-2026-46111","title":"Bluetooth: hci_conn: fix potential UAF in create_big_sync","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_conn: fix potential UAF in create_big_sync\n\nAdd hci_conn_valid() check in create_big_sync() to detect stale\nconnections before proceeding with BIG creati…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= eca0ae4aea66914515e5e3098ea051b518ee5316 < d41093723e47255d7d74df86e2736711c1b8486e","Linux >= eca0ae4aea66914515e5e3098ea051b518ee5316 < 6823f730bf195fc296d9edd09e2ca94bc1ff5584","Linux >= eca0ae4aea66914515e5e3098ea051b518ee5316 < 1750a2df0eab61dc421a7afae74abdd239a44b85","Linux >= eca0ae4aea66914515e5e3098ea051b518ee5316 < dc34f8d8240f25dd137dc2758ebbcc75e3779142","Linux >= eca0ae4aea66914515e5e3098ea051b518ee5316 < f8eaf92c57ad99358dd372580d5ff87623343a72","Linux >= eca0ae4aea66914515e5e3098ea051b518ee5316 < 0beddb0c380bed5f5b8e61ddbe14635bb73d0b41","Linux 6.0"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T15:19:42.422242Z"},"published":"2026-05-28","updated":"2026-10-16","sourceUpdated":"2026-10-16T15:20:51.197Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-46111","references":[{"url":"https://git.kernel.org/stable/c/d41093723e47255d7d74df86e2736711c1b8486e"},{"url":"https://git.kernel.org/stable/c/6823f730bf195fc296d9edd09e2ca94bc1ff5584"},{"url":"https://git.kernel.org/stable/c/1750a2df0eab61dc421a7afae74abdd239a44b85"},{"url":"https://git.kernel.org/stable/c/dc34f8d8240f25dd137dc2758ebbcc75e3779142"},{"url":"https://git.kernel.org/stable/c/f8eaf92c57ad99358dd372580d5ff87623343a72"},{"url":"https://git.kernel.org/stable/c/0beddb0c380bed5f5b8e61ddbe14635bb73d0b41"}],"tags":["cve.org"],"epss":0.00171,"epssPercentile":0.0604,"ingestedAt":"2026-10-16T17:24:46.706Z","slug":"CVE-2026-46111","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: hci_conn: fix potential UAF in create_big_sync\n\nAdd hci_conn_valid() check in create_big_sync() to detect stale\nconnections before proceeding with BIG creation. Handle the\nresulting -ECANCELED in create_big_complete() and re-validate the\nconnection under hci_dev_lock() before dereferencing, matching the\npattern used by create_le_conn_complete() and create_pa_complete().\n\nKeep the hci_conn object alive across the async boundary by taking\na reference via hci_conn_get() when queueing create_big_sync(), and\ndropping it in the completion callback. The refcount and the lock\nare complementary: the refcount keeps the object allocated, while\nhci_dev_lock() serializes hci_conn_hash_del()'s list_del_rcu() on\nhdev->conn_hash, as required by hci_conn_del().\n\nhci_conn_put() is called outside hci_dev_unlock() so the final put\n(which resolves to kfree() via bt_link_release) does not run under\nhdev->lock, though the release path would be safe either way.\n\nWithout this, create_big_complete() would unconditionally\ndereference the conn pointer on error, causing a use-after-free\nvia hci_connect_cfm() and hci_conn_del().\n\n## Affected\n\n- `Linux >= eca0ae4aea66914515e5e3098ea051b518ee5316 < d41093723e47255d7d74df86e2736711c1b8486e`\n- `Linux >= eca0ae4aea66914515e5e3098ea051b518ee5316 < 6823f730bf195fc296d9edd09e2ca94bc1ff5584`\n- `Linux >= eca0ae4aea66914515e5e3098ea051b518ee5316 < 1750a2df0eab61dc421a7afae74abdd239a44b85`\n- `Linux >= eca0ae4aea66914515e5e3098ea051b518ee5316 < dc34f8d8240f25dd137dc2758ebbcc75e3779142`\n- `Linux >= eca0ae4aea66914515e5e3098ea051b518ee5316 < f8eaf92c57ad99358dd372580d5ff87623343a72`\n- `Linux >= eca0ae4aea66914515e5e3098ea051b518ee5316 < 0beddb0c380bed5f5b8e61ddbe14635bb73d0b41`\n- `Linux 6.0`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}