{"id":"CVE-2026-31513","revision":"8c5b3bae53e541eea7a10804a97f5f50","records":[{"revision":"8c5b3bae53e541eea7a10804a97f5f50","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-31513","aliases":[],"title":"Bluetooth: L2CAP: Fix stack-out-of-bounds read in l2cap_ecred_conn_req","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: Fix stack-out-of-bounds read in l2cap_ecred_conn_req\n\nSyzbot reported a KASAN stack-out-of-bounds read in l2cap_build_cmd()\nthat is triggered by a malformed Enhanced Credit Based Connection Request.\n\nThe vulnerability stems from l2cap_ecred_conn_req(). The function allocates\na local stack buffer (`pdu`) designed to hold a maximum of 5 Source Channel\nIDs (SCIDs), totaling 18 bytes. When an attacker sends a request with more\nthan 5 SCIDs, the function calculates `rsp_len` based on this unvalidated\n`cmd_len` before checking if the number of SCIDs exceeds\nL2CAP_ECRED_MAX_CID.\n\nIf the SCID count is too high, the function correctly jumps to the\n`response` label to reject the packet, but `rsp_len` retains the\nattacker's oversized value. Consequently, l2cap_send_cmd() is instructed\nto read past the end of the 18-byte `pdu` buffer, triggering a\nKASAN panic.\n\nFix this by moving the assignment of `rsp_len` to after the `num_scid`\nboundary check. If the packet is rejected, `rsp_len` will safely\nremain 0, and the error response will only read the 8-byte base header\nfrom the stack.","state":0,"publishedAt":"2026-04-22T13:54:30.835+00:00","modifiedAt":"2026-10-19T18:45:54.652+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/bluetooth/l2cap_core.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"935f324e4b2461df2cf7f02b4195082b4304c708\",\n                            \"lessThan\": \"c8e1a27edb8b4e5afb56b384acd7b6c2dec1b7cc\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"e981a9392800ce2c5bca196a6ab2c55e9370efaa\",\n                            \"lessThan\": \"5b35f8211a913cfe7ab9d54fa36a272d2059a588\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f3fdf2e7276a3edc5df55454275da20eac186970\",\n                            \"lessThan\": \"a3d9c50d69785ae02e153f000da1b5fd6dbfdf1b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"c28d2bff70444a85b3b86aaf241ece9408c7858c\",\n                            \"lessThan\": \"9d87cb22195b2c67405f5485d525190747ad5493\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/bluetooth/l2cap_core.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.12.75\",\n                            \"lessThan\": \"6.12.80\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.16\",\n                            \"lessThan\": \"6.18.21\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.19.6\",\n                            \"lessThan\": \"6.19.11\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"semver\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H","score":8.1,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/c8e1a27edb8b4e5afb56b384acd7b6c2dec1b7cc","https://git.kernel.org/stable/c/5b35f8211a913cfe7ab9d54fa36a272d2059a588","https://git.kernel.org/stable/c/a3d9c50d69785ae02e153f000da1b5fd6dbfdf1b","https://git.kernel.org/stable/c/9d87cb22195b2c67405f5485d525190747ad5493"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-31513","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-31513","identifiers":["CVE-2026-31513"]},"retained":false,"historicalAffected":[]}],"coverage":[]}