{"id":"CVE-2026-98239","revision":"186859cbe1e3482da0906718a4d12439","records":[{"revision":"186859cbe1e3482da0906718a4d12439","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-98239","aliases":[],"title":"net: lan743x: fix RX checksum use-after-free","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: lan743x: fix RX checksum use-after-free\n\nlan743x_rx_process_buffer() adds each non-first receive buffer to the\nhead skb's frag_list.  On the last descriptor, lan743x_rx_trim_skb()\nlinearizes the head and frees the fragment skb metadata.\n\nThe checksum-success path then writes ip_summed through the local skb\npointer, which still points to the final fragment.  This causes a\nuse-after-free write when a packet spans more than one receive buffer.\n\nSet ip_summed on the surviving head skb instead.  Multi-buffer receive\ncan occur after a live MTU increase because existing ring entries keep\ntheir old buffer size until they are replenished.\n\nA KUnit test invoking lan743x_rx_process_buffer() with a two-buffer\npacket produced a one-byte KASAN use-after-free write before this change.\nThe same test passed after the change.  The driver object also builds\nwith W=1.  This was not tested on physical LAN743x hardware.","state":0,"publishedAt":"2026-10-06T08:45:10.611+00:00","modifiedAt":"2026-10-19T09:16:10.911+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/net/ethernet/microchip/lan743x_main.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"cd6910501cfd9a3bdff2f5fc33c9f3cf165ca54a\",\n                            \"lessThan\": \"0e52886c4324c9897c2c62f92be3dc8316cee67e\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"cd6910501cfd9a3bdff2f5fc33c9f3cf165ca54a\",\n                            \"lessThan\": \"a58024835c704419bb46d2a34e5223f65605f958\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"cd6910501cfd9a3bdff2f5fc33c9f3cf165ca54a\",\n                            \"lessThan\": \"6fe5c3a2503983abb431d93faeadfc7f5e6a7e33\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"cd6910501cfd9a3bdff2f5fc33c9f3cf165ca54a\",\n                            \"lessThan\": \"5c216bfa9fb7b36804485e67975e9c98055b31ef\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"cd6910501cfd9a3bdff2f5fc33c9f3cf165ca54a\",\n                            \"lessThan\": \"161a403c8625e152de03d1da22bbf9cda6dc9f9f\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"cd6910501cfd9a3bdff2f5fc33c9f3cf165ca54a\",\n                            \"lessThan\": \"a9ce4053dc945c5372dedba5017ee675b30dc0c5\",\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/net/ethernet/microchip/lan743x_main.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"6.1\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"6.1\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.189\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.158\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.112\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.54\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.8\",\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":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H","score":8.1,"severity":"HIGH"}],"references":["https://git.kernel.org/stable/c/0e52886c4324c9897c2c62f92be3dc8316cee67e","https://git.kernel.org/stable/c/a58024835c704419bb46d2a34e5223f65605f958","https://git.kernel.org/stable/c/6fe5c3a2503983abb431d93faeadfc7f5e6a7e33","https://git.kernel.org/stable/c/5c216bfa9fb7b36804485e67975e9c98055b31ef","https://git.kernel.org/stable/c/161a403c8625e152de03d1da22bbf9cda6dc9f9f","https://git.kernel.org/stable/c/a9ce4053dc945c5372dedba5017ee675b30dc0c5"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98239","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98239","identifiers":["CVE-2026-98239"]},"retained":false,"historicalAffected":[]}],"coverage":[]}