{"id":"CVE-2026-90074","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: fq_pie: clamp default quantum to avoid signed overflow\n\nfq_pie_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) without\nclamping","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: fq_pie: clamp default quantum to avoid signed overflow\n\nfq_pie_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) without\nclamping. A device with a huge MTU…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < 1f43e4dbc93b7d02761a024d5f895df823c07b72","Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < f7942b2693bc24c7d609a03d06f97bee3b0bd96a","Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < 6f1be05faecef4c0f9a008200209f66ef2e133f7","Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < 435da3734a8e63d3067016accc977ed1d10aaaa0","Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < 44dad8fe99b58a7fe2961e9eec6a5f07ace5b51f","Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < 044fa2498bbc2900f0c48a6ef2fdd5b2bdfc3795","Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < bf97fd2163ad1191ef8daa3d4df8372aee19e396","Linux >= ec97ecf1ebe485a17cd8395a5f35e6b80b57665a < c86cd7ed0b0e44779a3d1683f03e4353baf4bdc9","Linux 5.6"],"published":"2026-09-17","updated":"2026-09-17","sourceUpdated":"2026-09-17T17:16:56.530","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-90074","references":[{"url":"https://git.kernel.org/stable/c/044fa2498bbc2900f0c48a6ef2fdd5b2bdfc3795","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/1f43e4dbc93b7d02761a024d5f895df823c07b72","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/435da3734a8e63d3067016accc977ed1d10aaaa0","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/44dad8fe99b58a7fe2961e9eec6a5f07ace5b51f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/6f1be05faecef4c0f9a008200209f66ef2e133f7","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/bf97fd2163ad1191ef8daa3d4df8372aee19e396","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c86cd7ed0b0e44779a3d1683f03e4353baf4bdc9","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f7942b2693bc24c7d609a03d06f97bee3b0bd96a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"ingestedAt":"2026-09-17T16:21:47.898Z","epss":0.0021,"epssPercentile":0.11544,"slug":"CVE-2026-90074","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: fq_pie: clamp default quantum to avoid signed overflow\n\nfq_pie_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) without\nclamping. A device with a huge MTU (e.g. dummy with max_mtu == 0\naccepting MTU 2147483634) makes psched_mtu() return 0x80000000, which\noverflows the signed flow->deficit to INT_MIN in fq_pie_qdisc_dequeue(),\ncausing an infinite loop and soft lockup. Emulate fq_pie_policy which\nis already bounded to [1, 1 << 20]; clamp the default to [256, 1 << 20].\n256 matches fq_codel's floor and is a sane minimum for a DRR quantum.\n\nConditions to recreate the bug: a device whose MTU (plus\nhard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy\ndevice with max_mtu == 0 accepting MTU 2147483634). Requires\nCAP_NET_ADMIN in a user namespace.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}