{"id":"CVE-2026-80760","title":"Bluetooth: MGMT: reject HCI_CMD_SYNC params_len above 255","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: MGMT: reject HCI_CMD_SYNC params_len above 255\n\nmgmt_hci_cmd_sync() checks that the message length agrees with params_len\nbut puts no upper bound on it. para…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 827af4787e74e8df9e8e0677a69fbb15e0856d2f < b7d9edcf9fe6e9ec3a2e80ef9e8d44ef9b4f2894","Linux >= 827af4787e74e8df9e8e0677a69fbb15e0856d2f < 0bd0195ce25737cbdd0eabc54319ee0ddf3a0ad2","Linux >= 827af4787e74e8df9e8e0677a69fbb15e0856d2f < 6e1c44878aa3ee7336efeaf01414b030b0a5c273","Linux >= 827af4787e74e8df9e8e0677a69fbb15e0856d2f < 5d95286b6d6e8f1d304da7522bfa6860fc017e48","Linux 6.13"],"published":"2026-09-04","updated":"2026-10-19","sourceUpdated":"2026-10-19T08:43:16.923Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-80760","references":[{"url":"https://git.kernel.org/stable/c/b7d9edcf9fe6e9ec3a2e80ef9e8d44ef9b4f2894"},{"url":"https://git.kernel.org/stable/c/0bd0195ce25737cbdd0eabc54319ee0ddf3a0ad2"},{"url":"https://git.kernel.org/stable/c/6e1c44878aa3ee7336efeaf01414b030b0a5c273"},{"url":"https://git.kernel.org/stable/c/5d95286b6d6e8f1d304da7522bfa6860fc017e48"}],"tags":["cve.org"],"epss":0.00209,"epssPercentile":0.10293,"ingestedAt":"2026-10-19T10:20:54.950Z","slug":"CVE-2026-80760","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: MGMT: reject HCI_CMD_SYNC params_len above 255\n\nmgmt_hci_cmd_sync() checks that the message length agrees with params_len\nbut puts no upper bound on it. params_len is __le16 while the parameter\nlength in the HCI command header is a u8:\n\n\tstruct hci_command_hdr {\n\t\t__le16\topcode;\n\t\t__u8\tplen;\n\t} __packed;\n\nhci_cmd_sync_alloc() assigns one to the other:\n\n\thdr->plen = plen;\n\n\tif (plen)\n\t\tskb_put_data(skb, param, plen);\n\nso a params_len of 256 leaves plen at 0 while all 256 bytes are still\nappended. The frame handed to the driver then declares no parameters and\ncarries 256 of them. On a length framed transport such as H:4 the\ncontroller takes the trailing bytes as the start of the next packet.\n\nThe mgmt socket MTU is HCI_MAX_FRAME_SIZE, so params_len can reach about\n1KB this way. Commit 03f1700b9b4d (\"Bluetooth: MGMT: reject malformed\nHCI_CMD_SYNC commands\") only made params_len agree with the message\nlength, a value that fits the message but not the header field is still\naccepted.\n\nReject params_len that does not fit the header field.\n\n## Affected\n\n- `Linux >= 827af4787e74e8df9e8e0677a69fbb15e0856d2f < b7d9edcf9fe6e9ec3a2e80ef9e8d44ef9b4f2894`\n- `Linux >= 827af4787e74e8df9e8e0677a69fbb15e0856d2f < 0bd0195ce25737cbdd0eabc54319ee0ddf3a0ad2`\n- `Linux >= 827af4787e74e8df9e8e0677a69fbb15e0856d2f < 6e1c44878aa3ee7336efeaf01414b030b0a5c273`\n- `Linux >= 827af4787e74e8df9e8e0677a69fbb15e0856d2f < 5d95286b6d6e8f1d304da7522bfa6860fc017e48`\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":[]}