{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2026-90075",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-90075",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-09-17T16:05:54.851Z",
    "updatedAt": "2026-10-19T08:57:32.110Z",
    "importedAt": "2026-10-24T01:58:35.090Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "net/sched: fq_codel: clamp default quantum and mtu",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: fq_codel: clamp default quantum and mtu\n\nfq_codel_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_codel_dequeue(),\ncausing an infinite loop and soft lockup. Emulate fq_codel_change()\nand constrain to [256, FQ_CODEL_QUANTUM_MAX].\n\nThe same unclamped psched_mtu() is assigned to q->cparams.mtu a bit\nbelow, and fq_codel_change() never updates it. codel_should_drop()\ntests \"*backlog <= params->mtu\"; with mtu == 0x80000000 (~2 GiB) and\nthe default 32 MiB memory_limit, the test is always true, so CoDel is\nsilently and completely disabled (no drops, no ECN). Declare a single\nclamped mtu and assign both q->quantum and q->cparams.mtu from it,\nwhich also removes the double psched_mtu() call.\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.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe",
              "status": "affected",
              "versionType": "git",
              "lessThan": "d315ee8a07fd1810880227319cf60e6cd925ef22"
            },
            {
              "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a9a5b2943a00df2ab81a2209f31dd9e87016f120"
            },
            {
              "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe",
              "status": "affected",
              "versionType": "git",
              "lessThan": "3782067ec0d485628b6f1f9ede3eeeb4f611fcf2"
            },
            {
              "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe",
              "status": "affected",
              "versionType": "git",
              "lessThan": "397e2b1f71d9f15b8b4e47d24eb620e4dff8878d"
            },
            {
              "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe",
              "status": "affected",
              "versionType": "git",
              "lessThan": "324f86806673ae4a55f66d28db84577f46f615e1"
            },
            {
              "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe",
              "status": "affected",
              "versionType": "git",
              "lessThan": "dfb4b61db886917244284b18b44b23d2254b82c2"
            },
            {
              "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe",
              "status": "affected",
              "versionType": "git",
              "lessThan": "9f499e5827fdb6d7fdb46a7ce731852f6b1a1bb9"
            },
            {
              "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe",
              "status": "affected",
              "versionType": "git",
              "lessThan": "d9ebd8f9aa8b2773235889cb903fafd61f2d8585"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "3.5",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "3.5"
            },
            {
              "version": "5.10.270",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.15.221",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.188",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.157",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.110",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.18.52",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "7.2.6",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "7.2.*"
            },
            {
              "version": "7.3",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}