{"id":"CVE-2026-64557","summary":"Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_new_connection_cb()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: Fix use-after-free in l2cap_sock_new_connection_cb()\n\nl2cap_sock_new_connection_cb() returned l2cap_pi(sk)-\u003echan after\nrelease_sock(parent). Once the parent lock is dropped the newly\nenqueued child socket sk is reachable via the accept queue, so another\ntask can accept and free it before the callback dereferences sk,\nresulting in a use-after-free.\n\nRework the -\u003enew_connection() op so the core, rather than the callback,\nowns the child channel's lifetime. The op now receives a pre-allocated\nnew_chan and returns an errno instead of allocating and returning a\nchannel. l2cap_new_connection() allocates the child channel and links\nit into the conn list via __l2cap_chan_add() before invoking the\ncallback, so the conn-list reference keeps the channel alive once\nrelease_sock(parent) exposes the socket to other tasks.\n\nChannel configuration that was duplicated in l2cap_sock_init() and the\nvarious new_connection callbacks is consolidated into\nl2cap_chan_set_defaults(), which now inherits from the parent channel\nwhen one is supplied.","modified":"2026-08-18T03:31:10.174516269Z","published":"2026-07-29T08:01:47.462Z","related":["openSUSE-SU-2026:11476-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64557.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/36da806f7fbaee56ad9e81859deec203f9728700"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6fef032af0092ed5ccb767239a9ac1bc38c08a40"},{"type":"WEB","url":"https://git.kernel.org/stable/c/733e76e74e406c1d1ddc7369420dd8a47f48bb8a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/84e718b6a814edc84159361f9f454a4e92ae91ae"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8c37e4338c801ebb8cee52436c01c41e009f6e87"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b39298044e5534612511a2ff5de03ba5f6e7a820"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64557.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64557"},{"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":"8ffb929098a56939ac71509302eeab5b207bf262"},{"fixed":"b39298044e5534612511a2ff5de03ba5f6e7a820"},{"fixed":"8c37e4338c801ebb8cee52436c01c41e009f6e87"},{"fixed":"84e718b6a814edc84159361f9f454a4e92ae91ae"},{"fixed":"36da806f7fbaee56ad9e81859deec203f9728700"},{"fixed":"733e76e74e406c1d1ddc7369420dd8a47f48bb8a"},{"fixed":"6fef032af0092ed5ccb767239a9ac1bc38c08a40"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64557.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.13.0"},{"fixed":"6.1.178"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.145"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.97"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.40"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64557.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}