{"id":"CVE-2026-99013","title":"Bluetooth: ISO: Reject concurrent BIS listener setup","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: ISO: Reject concurrent BIS listener setup\n\niso_sock_listen() drops the socket lock before calling iso_listen_bis()\nto preserve the hdev->lock ordering. Two c…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= c541d7b5e17987ed330798b07d4ad508859c1c93 < 559e4d2b6f83aaa96061659cc7104b7a0293f9ef","Linux >= 168e28305b871d8ec604a8f51f35467b8d7ba05b < 90b744066ca520d1a6a505a11ade9c9a5f48accf","Linux >= 168e28305b871d8ec604a8f51f35467b8d7ba05b < 79993e9919a87068183ba3622c383f05c049c4bc","Linux >= 168e28305b871d8ec604a8f51f35467b8d7ba05b < 555ff78fa719f50ff4cdbdb40aa1acc6e8e327d3","Linux >= 6.12.6 < 6.12.113","Linux 6.13"],"published":"2026-10-23","updated":"2026-10-23","sourceUpdated":"2026-10-23T12:20:38.612Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-99013","references":[{"url":"https://git.kernel.org/stable/c/559e4d2b6f83aaa96061659cc7104b7a0293f9ef"},{"url":"https://git.kernel.org/stable/c/90b744066ca520d1a6a505a11ade9c9a5f48accf"},{"url":"https://git.kernel.org/stable/c/79993e9919a87068183ba3622c383f05c049c4bc"},{"url":"https://git.kernel.org/stable/c/555ff78fa719f50ff4cdbdb40aa1acc6e8e327d3"}],"tags":["cve.org"],"ingestedAt":"2026-10-23T13:24:55.536Z","slug":"CVE-2026-99013","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: ISO: Reject concurrent BIS listener setup\n\niso_sock_listen() drops the socket lock before calling iso_listen_bis()\nto preserve the hdev->lock ordering. Two concurrent listen() calls on\nthe same broadcast socket can therefore both observe BT_BOUND. Caller\nA can attach connA and release the locks, then caller B can acquire\nthem and attach connB before A publishes BT_LISTEN.\n\n__iso_chan_add() checks whether connB already has a socket, but not\nwhether the socket already has a connection. The second attachment\noverwrites iso_pi(sk)->conn, leaking the connA reference and leaving\nconnA->sk intact. Socket teardown follows connB, so later events on\nconnA can cause a stale socket access.\n\nRecheck BT_BOUND and require iso_pi(sk)->conn to be NULL after taking\nboth the HCI device and socket locks in iso_listen_bis(). The connection\ncheck also covers the interval between attachment and publication of\nBT_LISTEN. Reject a competing setup with -EBADFD through the existing\nunlock path before allocating another connection.\n\nA recorded KASAN report from an instrumented kernel shows:\n\n  BUG: KASAN: slab-use-after-free in iso_sock_hold+0x119/0x1f0\n  Call Trace:\n   iso_sock_hold+0x119/0x1f0\n   iso_conn_del+0xe4/0x270\n   hci_disconn_complete_evt+0x351/0x8c0\n   hci_event_packet+0x71b/0xb20\n   hci_rx_work+0x293/0x730\n\n  Allocated by task 93:\n   sk_prot_alloc+0x113/0x220\n   sk_alloc+0x2b/0x6d0\n   bt_sock_alloc+0x29/0x370\n   iso_sock_alloc.constprop.0+0x19/0x300\n   iso_sock_create+0x94/0x100\n\n  Freed by task 93:\n   kfree+0x121/0x3c0\n   __sk_destruct+0x42b/0x540\n   iso_sock_release+0x29d/0x340\n   __sock_release+0xa1/0x260\n   sock_close+0x10/0x20\n\n## Affected\n\n- `Linux >= c541d7b5e17987ed330798b07d4ad508859c1c93 < 559e4d2b6f83aaa96061659cc7104b7a0293f9ef`\n- `Linux >= 168e28305b871d8ec604a8f51f35467b8d7ba05b < 90b744066ca520d1a6a505a11ade9c9a5f48accf`\n- `Linux >= 168e28305b871d8ec604a8f51f35467b8d7ba05b < 79993e9919a87068183ba3622c383f05c049c4bc`\n- `Linux >= 168e28305b871d8ec604a8f51f35467b8d7ba05b < 555ff78fa719f50ff4cdbdb40aa1acc6e8e327d3`\n- `Linux >= 6.12.6 < 6.12.113`\n- `Linux 6.13`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}