{"id":"CVE-2026-74540","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-74540","summary":"Bluetooth: L2CAP: fix UAF in l2cap_le_connect_rsp","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: fix UAF in l2cap_le_connect_rsp\n\nl2cap_le_connect_rsp() obtains a channel via\n__l2cap_get_chan_by_ident() but neither holds a reference nor uses\nl2cap_chan_hold_unless_zero() before locking and operating on it.\nA concurrent l2cap_chan_del() triggered by a remote disconnect can\nfree the channel between the lookup and l2cap_chan_lock(), causing\na use-after-free.\n\nThe BR/EDR counterpart l2cap_connect_rsp() and the sibling handler\nl2cap_le_command_rej() already use l2cap_chan_hold_unless_zero()\nto safely hold a reference, but l2cap_le_connect_rsp() was left\nunprotected.\n\nFix by adding l2cap_chan_hold_unless_zero() after the ident lookup\nand l2cap_chan_put() on the exit path, consistent with other L2CAP\nresponse handlers.","published":"2026-08-15T12:27:51.522Z","modified":"2026-08-18T03:56:51.260299511Z","cvss":{"score":8.8,"severity":"HIGH","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"Linux","name":"Kernel","fixedVersion":"6.6.151"}],"fix":null,"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/09f447accc2570751e7d17f0dc0788b40d3edade"},{"type":"WEB","url":"https://git.kernel.org/stable/c/522b730c62c53a1981604fd73524697fd347830d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/58e3c5289ad230a7e24ae4b0c7b43f5ee6e32136"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c4740e7f23ff9a8210198d8b4703259e21b9f69d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fd4c1e301bdec60a40728ea37de531cbccda501a"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74540.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74540"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-18T03:56:51.260299511Z"}}