{"id":"CVE-2026-98009","title":"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","summary":"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 cra…","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-835"],"vendor":"Linux","product":"Linux","affected":["Linux >= dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33 < 440b66cc7b56ea38e9b878ae88da91992efaa4c4","Linux >= dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33 < 4ef8664eafafc8db68a1d52601f17dc008a223b7","Linux >= dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33 < 8b8d782c3b96376217087767dcf662cd3d25f226","Linux >= dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33 < 226d2702e74a570f5bfae6115b4706da4b94e5cf","Linux >= dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33 < 99ae477b892e203a37985ebc56f0063e072f7f4b","Linux >= dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33 < 8f80b113dea0bed3c1a31a4224b72775cd9ec52d","Linux >= dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33 < de22c30ec5598aca8797f02082d2ee1358dfa3ff","Linux >= dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33 < 1c38487f46b243bfeefec0c0c86023a3904f2214","Linux 5.6"],"published":"2026-09-25","updated":"2026-10-03","sourceUpdated":"2026-10-03T11:18:23.873","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-98009","references":[{"url":"https://git.kernel.org/stable/c/1c38487f46b243bfeefec0c0c86023a3904f2214","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/226d2702e74a570f5bfae6115b4706da4b94e5cf","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/440b66cc7b56ea38e9b878ae88da91992efaa4c4","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/4ef8664eafafc8db68a1d52601f17dc008a223b7","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/8b8d782c3b96376217087767dcf662cd3d25f226","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/8f80b113dea0bed3c1a31a4224b72775cd9ec52d","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/99ae477b892e203a37985ebc56f0063e072f7f4b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/de22c30ec5598aca8797f02082d2ee1358dfa3ff","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98009.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-98009"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2541140"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98009"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98009"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98009.mbox"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.00177,"epssPercentile":0.07163,"cvssSource":"vendor","ingestedAt":"2026-09-25T11:06:38.859Z","slug":"CVE-2026-98009","body":"## Overview\n\nIn 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<<20], 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\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Low · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-10-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98009.json)","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":212501,"id":"CVE-2026-98009","ts":1790668194174,"field":"cvss","old":null,"new":"5.5"},{"seq":212500,"id":"CVE-2026-98009","ts":1790668194174,"field":"severity","old":"none","new":"medium"}]}