{"id":"CVE-2026-23461","summary":"Bluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: Fix use-after-free in l2cap_unregister_user\n\nAfter commit ab4eedb790ca (\"Bluetooth: L2CAP: Fix corrupted list in\nhci_chan_del\"), l2cap_conn_del() uses conn-\u003elock to protect access to\nconn-\u003eusers. However, l2cap_register_user() and l2cap_unregister_user()\ndon't use conn-\u003elock, creating a race condition where these functions can\naccess conn-\u003eusers and conn-\u003ehchan concurrently with l2cap_conn_del().\n\nThis can lead to use-after-free and list corruption bugs, as reported\nby syzbot.\n\nFix this by changing l2cap_register_user() and l2cap_unregister_user()\nto use conn-\u003elock instead of hci_dev_lock(), ensuring consistent locking\nfor the l2cap_conn structure.","modified":"2026-10-28T02:30:53.051682612Z","published":"2026-04-03T15:15:41.051Z","related":["SUSE-SU-2026:2068-1","SUSE-SU-2026:21834-1","SUSE-SU-2026:21841-1","SUSE-SU-2026:21845-1","SUSE-SU-2026:21860-1","SUSE-SU-2026:21876-1","SUSE-SU-2026:21877-1","SUSE-SU-2026:21916-1","SUSE-SU-2026:21919-1","SUSE-SU-2026:2195-1","SUSE-SU-2026:2217-1","SUSE-SU-2026:2238-1","openSUSE-SU-2026:20826-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23461.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/11a87dd5df428a4b79a84d2790cac7f3c73f1f0d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/71030f3b3015a412133a805ff47970cdcf30c2b8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/752a6c9596dd25efd6978a73ff21f3b592668f4a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c22a5e659959eb77c2fbb58a5adfaf3c3dab7abf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/da3000cbe4851458a22be38bb18c0689c39fdd5f"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23461.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-23461"},{"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":"efc30877bd4bc85fefe98d80af60fafc86e5775e"},{"fixed":"11a87dd5df428a4b79a84d2790cac7f3c73f1f0d"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"f87271d21dd4ee83857ca11b94e7b4952749bbae"},{"fixed":"c22a5e659959eb77c2fbb58a5adfaf3c3dab7abf"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"ab4eedb790cae44313759b50fe47da285e2519d5"},{"fixed":"da3000cbe4851458a22be38bb18c0689c39fdd5f"},{"fixed":"71030f3b3015a412133a805ff47970cdcf30c2b8"},{"fixed":"752a6c9596dd25efd6978a73ff21f3b592668f4a"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6.6.84"},{"fixed":"6.6.130"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6.12.20"},{"fixed":"6.12.78"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6.13.8"},{"fixed":"6.14"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"18ab6b6078fa8191ca30a3065d57bf35d5635761"}]}],"versions":["v6.6.129","v6.6.128","v6.6.127","v6.6.126","v6.6.125","v6.6.124","v6.6.123","v6.6.122","v6.6.121","v6.6.120","v6.6.119","v6.6.118","v6.6.117","v6.6.116","v6.6.115","v6.6.114","v6.6.113","v6.6.112","v6.6.111","v6.6.110","v6.6.109","v6.6.108","v6.6.107","v6.6.106","v6.6.105","v6.6.104","v6.6.103","v6.6.102","v6.6.101","v6.6.100","v6.6.99","v6.6.98","v6.6.97","v6.6.96","v6.6.95","v6.6.94","v6.6.93","v6.6.92","v6.6.91","v6.6.90","v6.6.89","v6.6.88","v6.6.87","v6.6.86","v6.6.85","v6.6.84","v6.12.77","v6.12.76","v6.12.75","v6.12.74","v6.12.73","v6.12.72","v6.12.71","v6.12.70","v6.12.69","v6.12.68","v6.12.67","v6.12.66","v6.12.65","v6.12.64","v6.12.63","v6.12.62","v6.12.61","v6.12.60","v6.12.59","v6.12.58","v6.12.57","v6.12.56","v6.12.55","v6.12.54","v6.12.53","v6.12.52","v6.12.51","v6.12.50","v6.12.49","v6.12.48","v6.12.47","v6.12.46","v6.12.45","v6.12.44","v6.12.43","v6.12.42","v6.12.41","v6.12.40","v6.12.39","v6.12.38","v6.12.37","v6.12.36","v6.12.35","v6.12.34","v6.12.33","v6.12.32","v6.12.31","v6.12.30","v6.12.29","v6.12.28","v6.12.27","v6.12.26","v6.12.25","v6.12.24","v6.12.23","v6.12.22","v6.12.21","v6.12.20","v6.13.12","v6.13.11","v6.13.10","v6.13.9","v6.13.8"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-23461.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.130"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.78"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.20"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.14.0"},{"fixed":"6.19.10"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-23461.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}