{"id":"CVE-2026-74556","revision":"7a3b284046a845399d99755892cbf61b","records":[{"revision":"7a3b284046a845399d99755892cbf61b","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-74556","aliases":[],"title":"scsi: libiscsi_tcp: Bound SCSI Response data segment to the connection buffer","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nscsi: libiscsi_tcp: Bound SCSI Response data segment to the connection buffer\n\niscsi_tcp_hdr_dissect() receives the data segment of several PDU types\ninto the fixed-size conn->data buffer, which is allocated for\nISCSI_DEF_MAX_RECV_SEG_LEN (8192) bytes.  For the LOGIN_RSP, TEXT_RSP,\nREJECT and ASYNC_EVENT opcodes the dissect path already rejects a PDU\nwhose DataSegmentLength exceeds that buffer.\n\nThe SCSI Command Response (ISCSI_OP_SCSI_CMD_RSP) path also copies its\ndata segment (sense/response data) into conn->data via\niscsi_tcp_data_recv_prep(), but it does so without the same check.  The\nonly upstream bound on in.datalen is conn->max_recv_dlength, the\ninitiator's advertised MaxRecvDataSegmentLength, which is commonly\nnegotiated well above 8192 (open-iscsi defaults to 262144).  A target\nthat returns a SCSI Response with a DataSegmentLength between 8193 and\nmax_recv_dlength therefore overflows the 8192-byte conn->data buffer.\n\nOnce the same bound applies, ISCSI_OP_SCSI_CMD_RSP is handled exactly\nlike those responses: bound the data segment, receive it into conn->data\nwhen present, and otherwise complete the PDU with no data.  Fold the\nopcode into that case group rather than duplicating the check.","state":0,"publishedAt":"2026-08-15T12:28:01.359+00:00","modifiedAt":"2026-10-16T19:05:55.568+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                        \"drivers/scsi/libiscsi_tcp.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"a081c13e39b5c17052a7b46fafa61019c4c110ff\",\n                            \"lessThan\": \"a51812842084fd390590ab8dc0431f10c73ddc56\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a081c13e39b5c17052a7b46fafa61019c4c110ff\",\n                            \"lessThan\": \"a8f94cc9f0e5759252551be3a172960c57f21f54\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a081c13e39b5c17052a7b46fafa61019c4c110ff\",\n                            \"lessThan\": \"f1a3a51fc5dba0e99532379665069f1700da6b44\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a081c13e39b5c17052a7b46fafa61019c4c110ff\",\n                            \"lessThan\": \"c97b5265cc47775f77fd2a23d6bde0426997b233\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a081c13e39b5c17052a7b46fafa61019c4c110ff\",\n                            \"lessThan\": \"084af0253673425ce2ae62e3c7f74f0dd023711b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a081c13e39b5c17052a7b46fafa61019c4c110ff\",\n                            \"lessThan\": \"72815741715bd41556dac5eeb068bf0f8af06ee7\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a081c13e39b5c17052a7b46fafa61019c4c110ff\",\n                            \"lessThan\": \"b0aa3e8e2ab4ca92adb28a3ef41873b3363b8676\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a081c13e39b5c17052a7b46fafa61019c4c110ff\",\n                            \"lessThan\": \"c1dea15f819cded9b3faf58f8bec72323568b6e6\",\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                        \"drivers/scsi/libiscsi_tcp.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"2.6.29\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"2.6.29\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.265\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.216\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.183\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.151\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.103\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.44\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1.8\",\n                            \"lessThanOrEqual\": \"7.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2\",\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:N/S:U/C:H/I:H/A:H","score":9.8,"severity":"CRITICAL"}],"references":["https://git.kernel.org/stable/c/a51812842084fd390590ab8dc0431f10c73ddc56","https://git.kernel.org/stable/c/a8f94cc9f0e5759252551be3a172960c57f21f54","https://git.kernel.org/stable/c/f1a3a51fc5dba0e99532379665069f1700da6b44","https://git.kernel.org/stable/c/c97b5265cc47775f77fd2a23d6bde0426997b233","https://git.kernel.org/stable/c/084af0253673425ce2ae62e3c7f74f0dd023711b","https://git.kernel.org/stable/c/72815741715bd41556dac5eeb068bf0f8af06ee7","https://git.kernel.org/stable/c/b0aa3e8e2ab4ca92adb28a3ef41873b3363b8676","https://git.kernel.org/stable/c/c1dea15f819cded9b3faf58f8bec72323568b6e6"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-74556","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-74556","identifiers":["CVE-2026-74556"]},"retained":false,"historicalAffected":[]}],"coverage":[]}