{"id":"CVE-2026-98009","summary":"net/sched: ets: clamp quantum in parse and fallback paths","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: ets: clamp quantum in parse and fallback paths\n\nets_qdisc_change() falls back to psched_mtu() with no floor for bands\nwithout an explicit quantum. With a crafted size table qdisc_pkt_len\nreaches ~2 GiB, so a zero psched_mtu on a headerless device makes the\ndeficit-refill loop spin under the qdisc lock.\n\nMove the floor into ets_quantum_parse() so explicitly configured quanta\nare also clamped to [256, 1\u003c\u003c20], not just the fallback path.\n\nConditions to recreate the bug:\n  CONFIG_NET_SCH_ETS=y. Requires CAP_NET_ADMIN (namespace-local via\n  unshare -Urn suffices).\n\n  tc qdisc add dev dummy0 root ets bands 3 strict 2 quanta 1 1","modified":"2026-10-09T17:27:00.987749816Z","published":"2026-09-25T10:23:34.144Z","related":["openSUSE-SU-2026:12074-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98009.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/1c38487f46b243bfeefec0c0c86023a3904f2214"},{"type":"WEB","url":"https://git.kernel.org/stable/c/226d2702e74a570f5bfae6115b4706da4b94e5cf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/440b66cc7b56ea38e9b878ae88da91992efaa4c4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4ef8664eafafc8db68a1d52601f17dc008a223b7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8b8d782c3b96376217087767dcf662cd3d25f226"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8f80b113dea0bed3c1a31a4224b72775cd9ec52d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/99ae477b892e203a37985ebc56f0063e072f7f4b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/de22c30ec5598aca8797f02082d2ee1358dfa3ff"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98009.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98009"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33"},{"fixed":"440b66cc7b56ea38e9b878ae88da91992efaa4c4"},{"fixed":"4ef8664eafafc8db68a1d52601f17dc008a223b7"},{"fixed":"8b8d782c3b96376217087767dcf662cd3d25f226"},{"fixed":"226d2702e74a570f5bfae6115b4706da4b94e5cf"},{"fixed":"99ae477b892e203a37985ebc56f0063e072f7f4b"},{"fixed":"8f80b113dea0bed3c1a31a4224b72775cd9ec52d"},{"fixed":"de22c30ec5598aca8797f02082d2ee1358dfa3ff"},{"fixed":"1c38487f46b243bfeefec0c0c86023a3904f2214"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-98009.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.6.0"},{"fixed":"5.10.271"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.222"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.189"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.158"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.111"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.53"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.7"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-98009.json"}}],"schema_version":"1.9.0"}