{"id":"CVE-2026-98013","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: fq_pie: clamp quantum in change path\n\nfq_pie_change() accepts any quantum value from userspace, including 1.\nWith a crafted size table qdisc_pkt_len reaches …","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: fq_pie: clamp quantum in change path\n\nfq_pie_change() accepts any quantum value from userspace, including 1.\nWith a crafted size table qdisc_pkt_len reaches …","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-606"],"vendor":"Linux","product":"Linux","affected":["Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < ff4f3a0f3abd2ded467931d7da7984a68a768e0b","Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < 749aaebc1eb92ce2f38fd3caf68a2f99686d84ef","Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < 8fd98e56c41f79278eeb67512c28d7abc175bcf4","Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < 215df1e953ae72a09d425ec188e054058ae23dc9","Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < f90fe65b977e7aa9eb302230a09eb18f8c32ceaa","Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < c11e3a39807eb5a200445ae9082843ab86800415","Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < 6655b56e2801008566c594ef231f6c7b3f716c61","Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < 4864f58c53eb47257d55e01f47d4a9f355f7f970","Linux 5.6"],"published":"2026-09-25","updated":"2026-10-03","sourceUpdated":"2026-10-03T11:18:24.393","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-98013","references":[{"url":"https://git.kernel.org/stable/c/215df1e953ae72a09d425ec188e054058ae23dc9","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/4864f58c53eb47257d55e01f47d4a9f355f7f970","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6655b56e2801008566c594ef231f6c7b3f716c61","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/749aaebc1eb92ce2f38fd3caf68a2f99686d84ef","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/8fd98e56c41f79278eeb67512c28d7abc175bcf4","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c11e3a39807eb5a200445ae9082843ab86800415","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f90fe65b977e7aa9eb302230a09eb18f8c32ceaa","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ff4f3a0f3abd2ded467931d7da7984a68a768e0b","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98013.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-98013"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2541038"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98013"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98013"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-98013.mbox"}],"tags":["nvd","cve.org","csaf","vex","red-hat"],"epss":0.00176,"epssPercentile":0.07122,"cvssSource":"vendor","ingestedAt":"2026-09-25T11:06:38.858Z","slug":"CVE-2026-98013","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: fq_pie: clamp quantum in change path\n\nfq_pie_change() accepts any quantum value from userspace, including 1.\nWith a crafted size table qdisc_pkt_len reaches ~2 GiB, so quantum=1\nmakes the deficit-refill loop spin ~2^31 times under the qdisc lock\n(a soft lockup / denial of service).\n\nAdd max(256U, ...) matching fq_codel_change().\n\nConditions to recreate the bug:\n  CONFIG_NET_SCH_FQ_PIE=y. Requires CAP_NET_ADMIN (namespace-local via\n  unshare -Urn suffices).\n\n  tc qdisc add dev dummy0 root fq_pie\n  tc qdisc change dev dummy0 root fq_pie quantum 1 stab data 32768 size_log 15 cell_log 0\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** · Moderate · updated 2026-09-28 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-98013.json)","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":212515,"id":"CVE-2026-98013","ts":1790668195901,"field":"cvss","old":null,"new":"5.5"},{"seq":212514,"id":"CVE-2026-98013","ts":1790668195901,"field":"severity","old":"none","new":"medium"}]}