{
  "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-2026-31680",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-31680",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-04-25T08:46:56.807Z",
    "updatedAt": "2026-10-19T18:56:04.513Z",
    "importedAt": "2026-10-24T01:58:02.025Z",
    "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: ipv6: flowlabel: defer exclusive option free until RCU teardown",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ipv6: flowlabel: defer exclusive option free until RCU teardown\n\n`ip6fl_seq_show()` walks the global flowlabel hash under the seq-file\nRCU read-side lock and prints `fl->opt->opt_nflen` when an option block\nis present.\n\nExclusive flowlabels currently free `fl->opt` as soon as `fl->users`\ndrops to zero in `fl_release()`. However, the surrounding\n`struct ip6_flowlabel` remains visible in the global hash table until\nlater garbage collection removes it and `fl_free_rcu()` finally tears it\ndown.\n\nA concurrent `/proc/net/ip6_flowlabel` reader can therefore race that\nearly `kfree()` and dereference freed option state, triggering a crash\nin `ip6fl_seq_show()`.\n\nFix this by keeping `fl->opt` alive until `fl_free_rcu()`. That matches\nthe lifetime already required for the enclosing flowlabel while readers\ncan still reach it under RCU.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "d3aedd5ebd4b0b925b0bcda548066803e1318499",
              "status": "affected",
              "versionType": "git",
              "lessThan": "4b6798024f7b2d535f3db1002c760143cdbd1bd3"
            },
            {
              "version": "d3aedd5ebd4b0b925b0bcda548066803e1318499",
              "status": "affected",
              "versionType": "git",
              "lessThan": "3c54b66c83fb8fcbde8e6a7bf90b65856e39f827"
            },
            {
              "version": "d3aedd5ebd4b0b925b0bcda548066803e1318499",
              "status": "affected",
              "versionType": "git",
              "lessThan": "5a6b15f861b7c1304949e3350d23490a5fe429fd"
            },
            {
              "version": "d3aedd5ebd4b0b925b0bcda548066803e1318499",
              "status": "affected",
              "versionType": "git",
              "lessThan": "6c7fbdb8ffde6413640de7cfbd7c976c353e89f8"
            },
            {
              "version": "d3aedd5ebd4b0b925b0bcda548066803e1318499",
              "status": "affected",
              "versionType": "git",
              "lessThan": "8027964931785cb73d520ac70a342a3dc16c249b"
            },
            {
              "version": "d3aedd5ebd4b0b925b0bcda548066803e1318499",
              "status": "affected",
              "versionType": "git",
              "lessThan": "414726b69921fe6355ae453f5b35e68dd078342a"
            },
            {
              "version": "d3aedd5ebd4b0b925b0bcda548066803e1318499",
              "status": "affected",
              "versionType": "git",
              "lessThan": "572ce62778519a7d4d1c15f55dd2e45a474133c4"
            },
            {
              "version": "d3aedd5ebd4b0b925b0bcda548066803e1318499",
              "status": "affected",
              "versionType": "git",
              "lessThan": "9ca562bb8e66978b53028fa32b1a190708e6a091"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "3.9",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "3.9"
            },
            {
              "version": "5.10.253",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.15.203",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.168",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.134",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.81",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.18.22",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "6.19.12",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.19.*"
            },
            {
              "version": "7.0",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}