{"id":"CVE-2026-98950","revision":"4ed2129e50f04c579957dad86afd5564","records":[{"revision":"4ed2129e50f04c579957dad86afd5564","observedAt":"2026-10-23T16:01:20.601+00:00","statement":{"source":"cve-program","id":"CVE-2026-98950","aliases":[],"title":"flow_dissector: avoid u16 truncation of hlen in bpf_flow_dissect()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nflow_dissector: avoid u16 truncation of hlen in bpf_flow_dissect()\n\nbpf_flow_dissect() sanitizes the offsets returned by the BPF program\nwith clamp_t(u16, ..., hlen).\n\nIf hlen is bigger than 65535, the upper bound is truncated before\nthe comparison. For instance, with hlen == 65536, both nhoff and\nthoff are forced to zero, even if the program returned sane values.\n\nThis is the same class of bug as the one fixed in commit 99bda1ecbd56\n(\"flow_dissector: avoid u16 truncation of skb->len when computing\nthoff\"). That fix does not cover the BPF path, because\n__skb_flow_dissect() returns early when a BPF flow dissector\nhandles the packet.\n\nstruct bpf_flow_keys stores nhoff and thoff as u16, so cap hlen\nto U16_MAX before clamping.\n\nFound by sashiko while reviewing the commit above.","state":0,"publishedAt":"2026-10-23T12:19:09.89+00:00","modifiedAt":"2026-10-23T12:19:09.89+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/core/flow_dissector.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9\",\n                            \"lessThan\": \"c44c02c930c6583b235a1937c69ff716c4bb4514\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9\",\n                            \"lessThan\": \"3fb5ad2951a6df92c98f4f06cd70f20c50a2eb2a\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9\",\n                            \"lessThan\": \"cc18eb0e9941162c03f03f411ed7f6c339d91fa0\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9\",\n                            \"lessThan\": \"61b43a51a55929ec040bee3ea51af2121b956d05\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"d58e468b1112dcd1d5193c0a89ff9f98b5a3e8b9\",\n                            \"lessThan\": \"f202578efc738b883cfa04889eb97328914265a7\",\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                        \"net/core/flow_dissector.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4.20\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"4.20\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.160\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.113\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.57\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.11\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/c44c02c930c6583b235a1937c69ff716c4bb4514","https://git.kernel.org/stable/c/3fb5ad2951a6df92c98f4f06cd70f20c50a2eb2a","https://git.kernel.org/stable/c/cc18eb0e9941162c03f03f411ed7f6c339d91fa0","https://git.kernel.org/stable/c/61b43a51a55929ec040bee3ea51af2121b956d05","https://git.kernel.org/stable/c/f202578efc738b883cfa04889eb97328914265a7"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98950","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98950","identifiers":["CVE-2026-98950"]},"retained":false,"historicalAffected":[]}],"coverage":[]}