{"id":"CVE-2026-31708","revision":"6cc7d66cd7dd47baa25d6ff6ca8a442e","records":[{"revision":"6cc7d66cd7dd47baa25d6ff6ca8a442e","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-31708","aliases":[],"title":"smb: client: fix OOB read in smb2_ioctl_query_info QUERY_INFO path","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: fix OOB read in smb2_ioctl_query_info QUERY_INFO path\n\nsmb2_ioctl_query_info() has two response-copy branches: PASSTHRU_FSCTL\nand the default QUERY_INFO path.  The QUERY_INFO branch clamps\nqi.input_buffer_length to the server-reported OutputBufferLength and then\ncopies qi.input_buffer_length bytes from qi_rsp->Buffer to userspace, but\nit never verifies that the flexible-array payload actually fits within\nrsp_iov[1].iov_len.\n\nA malicious server can return OutputBufferLength larger than the actual\nQUERY_INFO response, causing copy_to_user() to walk past the response\nbuffer and expose adjacent kernel heap to userspace.\n\nGuard the QUERY_INFO copy with a bounds check on the actual Buffer\npayload.  Use struct_size(qi_rsp, Buffer, qi.input_buffer_length)\nrather than an open-coded addition so the guard cannot overflow on\n32-bit builds.","state":0,"publishedAt":"2026-05-01T13:56:05.88+00:00","modifiedAt":"2026-10-19T19:06:06.825+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                        \"fs/smb/client/smb2ops.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"f5778c398713692a16150ae96e5c8270bab8399f\",\n                            \"lessThan\": \"e66bdc0704977ecee667a81d38255b579c2353d0\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f5778c398713692a16150ae96e5c8270bab8399f\",\n                            \"lessThan\": \"9e203dbb5402897c43130fb171a2617008a91f45\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f5778c398713692a16150ae96e5c8270bab8399f\",\n                            \"lessThan\": \"1dd757379997b71a328a4b591ffaf481acd0ead1\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f5778c398713692a16150ae96e5c8270bab8399f\",\n                            \"lessThan\": \"a34d456934fe42e4da5d2cc07787bf418bee99c6\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f5778c398713692a16150ae96e5c8270bab8399f\",\n                            \"lessThan\": \"ac2f14e4705d020f04e806efa0d49ab8dc2b145f\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f5778c398713692a16150ae96e5c8270bab8399f\",\n                            \"lessThan\": \"078fae8f50adebb903ccf2252b44391324571e78\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f5778c398713692a16150ae96e5c8270bab8399f\",\n                            \"lessThan\": \"85fd46ee26a11841c670449508025965f61ce131\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"f5778c398713692a16150ae96e5c8270bab8399f\",\n                            \"lessThan\": \"a58c5af19ff0d6f44f6e9fe31e33a2c92223f77e\",\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\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"fs/smb/client/smb2ops.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"5.1\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"5.1\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.259\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.210\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.175\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.136\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.84\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.25\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.0.2\",\n                            \"lessThanOrEqual\": \"7.0.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H","score":8.1,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/e66bdc0704977ecee667a81d38255b579c2353d0","https://git.kernel.org/stable/c/9e203dbb5402897c43130fb171a2617008a91f45","https://git.kernel.org/stable/c/1dd757379997b71a328a4b591ffaf481acd0ead1","https://git.kernel.org/stable/c/a34d456934fe42e4da5d2cc07787bf418bee99c6","https://git.kernel.org/stable/c/ac2f14e4705d020f04e806efa0d49ab8dc2b145f","https://git.kernel.org/stable/c/078fae8f50adebb903ccf2252b44391324571e78","https://git.kernel.org/stable/c/85fd46ee26a11841c670449508025965f61ce131","https://git.kernel.org/stable/c/a58c5af19ff0d6f44f6e9fe31e33a2c92223f77e"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-31708","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-31708","identifiers":["CVE-2026-31708"]},"retained":false,"historicalAffected":[]}],"coverage":[]}