{"schema":"threatline.record/2","record":{"id":"CVE-2026-98570","aliases":[],"summary":"net: ipv6: keep room for the mac header in dst_dev_overhead()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ipv6: keep room for the mac header in dst_dev_overhead()\n\nThe seg6, ioam6 and rpl lwtunnels size their skb_cow_head() request as\nthe length they are about to push plus dst_dev_overhead(), then push the\nnew headers and rebuild the mac header below them with\nskb_mac_header_rebuild().  That rebuild needs skb->mac_len of headroom,\nbut dst_dev_overhead() leaves LL_RESERVED_SPACE() of the egress device,\n16 bytes for plain Ethernet.\n\nWhere the mac header is longer than that, as it is on ingress through a\nVLAN device with reorder_hdr off, the rebuild runs out of room:\nskb_set_mac_header(skb, -skb->mac_len) computes a negative offset,\nstores it unchecked in the u16 skb->mac_header, and the memmove that\nfollows writes skb->mac_len bytes about 64 KB past skb->head.\nForwarding plain ping6 traffic through such a device reproduces it on\nall five seg6 encapsulation modes and on the rpl and ioam6 inline paths;\nskb->mac_header comes back as 65534 on a 704-byte head.\n\nReturn the larger of the two.  The helper already returns skb->mac_len\nwhen it has no dst, so this only makes the other branch agree, and it\ncovers every caller rather than each call site in turn.","categories":["Operating systems"],"product":"Linux","vendor":"Linux","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98570","source_modified_at":"2026-10-19T09:21:55.765Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"dce525185bc92864e5a318040285ee070563fe34","lessThan":"36c07127924f11fc5741a780abcaaf808fe9ef13","status":"affected","versionType":"git"},{"version":"dce525185bc92864e5a318040285ee070563fe34","lessThan":"87cd6b717e4069dca34e0866e57eaeb44d3b173e","status":"affected","versionType":"git"},{"version":"8471e228448a818e4c27cab4b681b2e758e46cf5","status":"affected","versionType":"git"},{"version":"c432cd18a07b623651ed15ea167bd303467004cc","status":"affected","versionType":"git"},{"version":"634710a372ba65bee667c2f6e58a97658c639eab","status":"affected","versionType":"git"},{"version":"c447c5a9c47bb4858ab12bf90879fe595d2b7f46","status":"affected","versionType":"git"},{"version":"ab9de9c48316d2622d3bf353916b99971570e2c9","status":"affected","versionType":"git"},{"version":"2fcc9f3798ef82399564d247458e69abd10e683b","status":"affected","versionType":"git"},{"version":"371d8dc298b4f59e99b4564ac5d906fce0932c69","status":"affected","versionType":"git"},{"version":"b26f015dfb07b6be12d005a0ed0c5c43b7bedbf3","status":"affected","versionType":"git"},{"version":"c0b11dc50590e10590b39dcda79835cd32f49d00","status":"affected","versionType":"git"},{"version":"4c12c3c8abd8b888945d31e7bdbb0d8b73032fc5","status":"affected","versionType":"git"},{"version":"25d8e065c7972dc98fd7a4cac322d5367eaede88","status":"affected","versionType":"git"},{"version":"4a855c5aec41bf84922224ab7a74e088776e3ac4","status":"affected","versionType":"git"},{"version":"a9f0407414e16176fdbbbd298c9e18d6dfdf96bc","status":"affected","versionType":"git"},{"version":"6.12.16","lessThan":"6.13","status":"affected","versionType":"semver"},{"version":"6.13.4","lessThan":"6.14","status":"affected","versionType":"semver"},{"version":"5.15.179","lessThan":"5.16","status":"affected","versionType":"semver"},{"version":"6.1.130","lessThan":"6.2","status":"affected","versionType":"semver"},{"version":"6.6.81","lessThan":"6.7","status":"affected","versionType":"semver"},{"version":"5.10.235","lessThan":"5.11","status":"affected","versionType":"semver"}],"defaultStatus":"unaffected"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98570","source_modified_at":"2026-10-19T09:21:55.765Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"Linux","vendor":"Linux","versions":[{"version":"6.14","status":"affected"},{"version":"0","lessThan":"6.14","status":"unaffected","versionType":"semver"},{"version":"7.2.9","lessThanOrEqual":"7.2.*","status":"unaffected","versionType":"semver"},{"version":"7.3","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}],"defaultStatus":"affected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98570","source_modified_at":"2026-10-19T09:21:55.765Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"36c07127924f11fc5741a780abcaaf808fe9ef13","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98570","source_modified_at":"2026-10-19T09:21:55.765Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"87cd6b717e4069dca34e0866e57eaeb44d3b173e","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98570","source_modified_at":"2026-10-19T09:21:55.765Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"6.13","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98570","source_modified_at":"2026-10-19T09:21:55.765Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"6.14","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98570","source_modified_at":"2026-10-19T09:21:55.765Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"5.16","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98570","source_modified_at":"2026-10-19T09:21:55.765Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"6.2","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98570","source_modified_at":"2026-10-19T09:21:55.765Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"6.7","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-98570","source_modified_at":"2026-10-19T09:21:55.765Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"Linux","ecosystem":null},"version":"5.11","basis":"first unaffected version stated in the CVE record"}],"cvss":null,"severity":null,"kev":{"listed":false},"epss":{"probability":0.00189,"percentile":0.08118,"score_date":"2026-10-23"},"published_at":"2026-10-18T15:18:36.308Z","modified_at":"2026-10-19T09:21:55.765Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-98570","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-10-19T09:21:55.765Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-98570","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://git.kernel.org/stable/c/36c07127924f11fc5741a780abcaaf808fe9ef13"},{"source":"CVE List","url":"https://git.kernel.org/stable/c/87cd6b717e4069dca34e0866e57eaeb44d3b173e"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-10-19T09:21:55.765Z","content_hash":"b64b8aed644650b8d92dbc24c4847228ab83c55356fbcdfce80ede3d48b18dda"}}