{"id":"CVE-2024-36968","title":"Bluetooth: L2CAP: Fix div-by-zero in l2cap_le_flowctl_init()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: Fix div-by-zero in l2cap_le_flowctl_init()\n\nl2cap_le_flowctl_init() can cause both div-by-zero and an integer\noverflow since hdev->le_mtu may not fall…","severity":"high","cvss":7.6,"cvssVector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 6ed58ec520ad2b2fe3f955c8a5fd0eecafccebdf < e34634fad3792d4d35850cae72b7b7813466844f","Linux >= 6ed58ec520ad2b2fe3f955c8a5fd0eecafccebdf < ad3f7986c5a0f82b8b66a0afe1cc1f5421e1d674","Linux >= 6ed58ec520ad2b2fe3f955c8a5fd0eecafccebdf < dfece2b4e3759759b2bdfac2cd6d0ee9fbf055f3","Linux >= 6ed58ec520ad2b2fe3f955c8a5fd0eecafccebdf < d2b2f7d3936dc5990549bc36ab7ac7ac37f22c30","Linux >= 6ed58ec520ad2b2fe3f955c8a5fd0eecafccebdf < 4d3dbaa252257d20611c3647290e6171f1bbd6c8","Linux >= 6ed58ec520ad2b2fe3f955c8a5fd0eecafccebdf < a5b862c6a221459d54e494e88965b48dcfa6cc44","Linux 2.6.39"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2024-06-12T14:43:17.673959Z"},"published":"2024-06-08","updated":"2026-10-30","sourceUpdated":"2026-10-30T12:18:28.225Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2024-36968","references":[{"url":"https://git.kernel.org/stable/c/e34634fad3792d4d35850cae72b7b7813466844f"},{"url":"https://git.kernel.org/stable/c/ad3f7986c5a0f82b8b66a0afe1cc1f5421e1d674"},{"url":"https://git.kernel.org/stable/c/dfece2b4e3759759b2bdfac2cd6d0ee9fbf055f3"},{"url":"https://git.kernel.org/stable/c/d2b2f7d3936dc5990549bc36ab7ac7ac37f22c30"},{"url":"https://git.kernel.org/stable/c/4d3dbaa252257d20611c3647290e6171f1bbd6c8"},{"url":"https://git.kernel.org/stable/c/a5b862c6a221459d54e494e88965b48dcfa6cc44"}],"tags":["cve.org"],"epss":0.00293,"epssPercentile":0.22072,"ingestedAt":"2026-11-03T12:44:28.818Z","slug":"CVE-2024-36968","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: Fix div-by-zero in l2cap_le_flowctl_init()\n\nl2cap_le_flowctl_init() can cause both div-by-zero and an integer\noverflow since hdev->le_mtu may not fall in the valid range.\n\nMove MTU from hci_dev to hci_conn to validate MTU and stop the connection\nprocess earlier if MTU is invalid.\nAlso, add a missing validation in read_buffer_size() and make it return\nan error value if the validation fails.\nNow hci_conn_add() returns ERR_PTR() as it can fail due to the both a\nkzalloc failure and invalid MTU value.\n\ndivide error: 0000 [#1] PREEMPT SMP KASAN NOPTI\nCPU: 0 PID: 67 Comm: kworker/u5:0 Tainted: G        W          6.9.0-rc5+ #20\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014\nWorkqueue: hci0 hci_rx_work\nRIP: 0010:l2cap_le_flowctl_init+0x19e/0x3f0 net/bluetooth/l2cap_core.c:547\nCode: e8 17 17 0c 00 66 41 89 9f 84 00 00 00 bf 01 00 00 00 41 b8 02 00 00 00 4c\n89 fe 4c 89 e2 89 d9 e8 27 17 0c 00 44 89 f0 31 d2 <66> f7 f3 89 c3 ff c3 4d 8d\nb7 88 00 00 00 4c 89 f0 48 c1 e8 03 42\nRSP: 0018:ffff88810bc0f858 EFLAGS: 00010246\nRAX: 00000000000002a0 RBX: 0000000000000000 RCX: dffffc0000000000\nRDX: 0000000000000000 RSI: ffff88810bc0f7c0 RDI: ffffc90002dcb66f\nRBP: ffff88810bc0f880 R08: aa69db2dda70ff01 R09: 0000ffaaaaaaaaaa\nR10: 0084000000ffaaaa R11: 0000000000000000 R12: ffff88810d65a084\nR13: dffffc0000000000 R14: 00000000000002a0 R15: ffff88810d65a000\nFS:  0000000000000000(0000) GS:ffff88811ac00000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 0000000020000100 CR3: 0000000103268003 CR4: 0000000000770ef0\nPKRU: 55555554\nCall Trace:\n <TASK>\n l2cap_le_connect_req net/bluetooth/l2cap_core.c:4902 [inline]\n l2cap_le_sig_cmd net/bluetooth/l2cap_core.c:5420 [inline]\n l2cap_le_sig_channel net/bluetooth/l2cap_core.c:5486 [inline]\n l2cap_recv_frame+0xe59d/0x11710 net/bluetooth/l2cap_core.c:6809\n l2cap_recv_acldata+0x544/0x10a0 net/bluetooth/l2cap_core.c:7506\n hci_acldata_packet net/bluetooth/hci_core.c:3939 [inline]\n hci_rx_work+0x5e5/0xb20 net/bluetooth/hci_core.c:4176\n process_one_work kernel/workqueue.c:3254 [inline]\n process_scheduled_works+0x90f/0x1530 kernel/workqueue.c:3335\n worker_thread+0x926/0xe70 kernel/workqueue.c:3416\n kthread+0x2e3/0x380 kernel/kthread.c:388\n ret_from_fork+0x5c/0x90 arch/x86/kernel/process.c:147\n ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244\n </TASK>\nModules linked in:\n---[ end trace 0000000000000000 ]---\n\n## Affected\n\n- `Linux >= 6ed58ec520ad2b2fe3f955c8a5fd0eecafccebdf < e34634fad3792d4d35850cae72b7b7813466844f`\n- `Linux >= 6ed58ec520ad2b2fe3f955c8a5fd0eecafccebdf < ad3f7986c5a0f82b8b66a0afe1cc1f5421e1d674`\n- `Linux >= 6ed58ec520ad2b2fe3f955c8a5fd0eecafccebdf < dfece2b4e3759759b2bdfac2cd6d0ee9fbf055f3`\n- `Linux >= 6ed58ec520ad2b2fe3f955c8a5fd0eecafccebdf < d2b2f7d3936dc5990549bc36ab7ac7ac37f22c30`\n- `Linux >= 6ed58ec520ad2b2fe3f955c8a5fd0eecafccebdf < 4d3dbaa252257d20611c3647290e6171f1bbd6c8`\n- `Linux >= 6ed58ec520ad2b2fe3f955c8a5fd0eecafccebdf < a5b862c6a221459d54e494e88965b48dcfa6cc44`\n- `Linux 2.6.39`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":42,"depthScoreParts":{"impact":41.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}