{"id":"CVE-2026-98009","state":"PUBLISHED","title":"net/sched: ets: clamp quantum in parse and fallback paths","description":"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<<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","publishedAt":"2026-09-25T10:23:34.144Z","updatedAt":"2026-10-19T09:12:14.751Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"440b66cc7b56ea38e9b878ae88da91992efaa4c4","versionType":"git"},{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"4ef8664eafafc8db68a1d52601f17dc008a223b7","versionType":"git"},{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"8b8d782c3b96376217087767dcf662cd3d25f226","versionType":"git"},{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"226d2702e74a570f5bfae6115b4706da4b94e5cf","versionType":"git"},{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"99ae477b892e203a37985ebc56f0063e072f7f4b","versionType":"git"},{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"8f80b113dea0bed3c1a31a4224b72775cd9ec52d","versionType":"git"},{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"de22c30ec5598aca8797f02082d2ee1358dfa3ff","versionType":"git"},{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"1c38487f46b243bfeefec0c0c86023a3904f2214","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/sch_ets.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.6","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.6","versionType":"semver"},{"version":"5.10.271","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.222","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.189","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.158","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.111","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.53","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.7","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/sch_ets.c"]}],"references":["https://git.kernel.org/stable/c/440b66cc7b56ea38e9b878ae88da91992efaa4c4","https://git.kernel.org/stable/c/4ef8664eafafc8db68a1d52601f17dc008a223b7","https://git.kernel.org/stable/c/8b8d782c3b96376217087767dcf662cd3d25f226","https://git.kernel.org/stable/c/226d2702e74a570f5bfae6115b4706da4b94e5cf","https://git.kernel.org/stable/c/99ae477b892e203a37985ebc56f0063e072f7f4b","https://git.kernel.org/stable/c/8f80b113dea0bed3c1a31a4224b72775cd9ec52d","https://git.kernel.org/stable/c/de22c30ec5598aca8797f02082d2ee1358dfa3ff","https://git.kernel.org/stable/c/1c38487f46b243bfeefec0c0c86023a3904f2214"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:43.249Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/98xxx/CVE-2026-98009.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-98009","state":"PUBLISHED","datePublished":"2026-09-25T10:23:34.144Z","dateUpdated":"2026-10-19T09:12:14.751Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-25T10:19:56.068Z"},"containers":{"cna":{"title":"net/sched: ets: clamp quantum in parse and fallback paths","descriptions":[{"lang":"en","value":"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<<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"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"440b66cc7b56ea38e9b878ae88da91992efaa4c4","versionType":"git"},{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"4ef8664eafafc8db68a1d52601f17dc008a223b7","versionType":"git"},{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"8b8d782c3b96376217087767dcf662cd3d25f226","versionType":"git"},{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"226d2702e74a570f5bfae6115b4706da4b94e5cf","versionType":"git"},{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"99ae477b892e203a37985ebc56f0063e072f7f4b","versionType":"git"},{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"8f80b113dea0bed3c1a31a4224b72775cd9ec52d","versionType":"git"},{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"de22c30ec5598aca8797f02082d2ee1358dfa3ff","versionType":"git"},{"version":"dcc68b4d8084e1ac9af0d4022d6b1aff6a139a33","status":"affected","lessThan":"1c38487f46b243bfeefec0c0c86023a3904f2214","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/sch_ets.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.6","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.6","versionType":"semver"},{"version":"5.10.271","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.222","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.189","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.158","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.111","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.53","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.7","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/sch_ets.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/440b66cc7b56ea38e9b878ae88da91992efaa4c4"},{"url":"https://git.kernel.org/stable/c/4ef8664eafafc8db68a1d52601f17dc008a223b7"},{"url":"https://git.kernel.org/stable/c/8b8d782c3b96376217087767dcf662cd3d25f226"},{"url":"https://git.kernel.org/stable/c/226d2702e74a570f5bfae6115b4706da4b94e5cf"},{"url":"https://git.kernel.org/stable/c/99ae477b892e203a37985ebc56f0063e072f7f4b"},{"url":"https://git.kernel.org/stable/c/8f80b113dea0bed3c1a31a4224b72775cd9ec52d"},{"url":"https://git.kernel.org/stable/c/de22c30ec5598aca8797f02082d2ee1358dfa3ff"},{"url":"https://git.kernel.org/stable/c/1c38487f46b243bfeefec0c0c86023a3904f2214"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T09:12:14.751Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.6","versionEndExcluding":"5.10.271"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.6","versionEndExcluding":"5.15.222"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.6","versionEndExcluding":"6.1.189"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.6","versionEndExcluding":"6.6.158"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.6","versionEndExcluding":"6.12.111"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.6","versionEndExcluding":"6.18.53"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.6","versionEndExcluding":"7.2.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.6","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}