{
  "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-2026-64538",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-64538",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-07-27T20:10:32.779Z",
    "updatedAt": "2026-10-15T01:23:51.777Z",
    "importedAt": "2026-10-24T01:58:25.636Z",
    "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": "ipv6: Fix null-ptr-deref in fib6_nh_mtu_change().",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: Fix null-ptr-deref in fib6_nh_mtu_change().\n\nfib6_nh_mtu_change() re-fetches idev via __in6_dev_get(arg->dev) and\ndereferences idev->cnf.mtu6 without a NULL check. addrconf_ifdown()\nclears dev->ip6_ptr with RCU_INIT_POINTER() after rt6_disable_ip() has\nreleased tb6_lock, so the RA-driven MTU walk can observe a NULL idev and\noops. The caller rt6_mtu_change_route() guards its own __in6_dev_get(),\nbut this re-fetch is unguarded; nexthop-backed routes survive\naddrconf_ifdown()'s flush, so the walk still reaches it after ip6_ptr is\nnulled.\n\nReturn 0 when idev is NULL, matching rt6_mtu_change_route() and the\nfib6_mtu() fix in commit 5ad509c1fdad (\"ipv6: Fix null-ptr-deref in\nfib6_mtu().\").\n\n  Oops: general protection fault, ... KASAN: null-ptr-deref in range\n        [0x00000000000002a8-0x00000000000002af]\n  RIP: 0010:fib6_nh_mtu_change+0x203/0x990\n   rt6_mtu_change_route+0x141/0x1d0\n   __fib6_clean_all+0xd0/0x160\n   rt6_mtu_change+0xb4/0x100\n   ndisc_router_discovery+0x24b5/0x2cb0\n   icmpv6_rcv+0x12e9/0x1710\n   ipv6_rcv+0x39b/0x410",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "c0b220cf7d80eb8a36ae9f12cae6df4577a6814e",
              "status": "affected",
              "versionType": "git",
              "lessThan": "d08d019f2f43a6f9a71e81868bbc326b3afaf37b"
            },
            {
              "version": "c0b220cf7d80eb8a36ae9f12cae6df4577a6814e",
              "status": "affected",
              "versionType": "git",
              "lessThan": "1451deca9896957159f0666520a792c1b861af4f"
            },
            {
              "version": "c0b220cf7d80eb8a36ae9f12cae6df4577a6814e",
              "status": "affected",
              "versionType": "git",
              "lessThan": "b2c70dd3326809429b709a9c7e9220d29923051a"
            },
            {
              "version": "c0b220cf7d80eb8a36ae9f12cae6df4577a6814e",
              "status": "affected",
              "versionType": "git",
              "lessThan": "302d57ed7872838b40e56a868fb4c7da7da606e9"
            },
            {
              "version": "c0b220cf7d80eb8a36ae9f12cae6df4577a6814e",
              "status": "affected",
              "versionType": "git",
              "lessThan": "80600b5d0f3ecb9324120dc95b5e915130f516c5"
            },
            {
              "version": "c0b220cf7d80eb8a36ae9f12cae6df4577a6814e",
              "status": "affected",
              "versionType": "git",
              "lessThan": "b0d0eb13a0441a8ebf4f227843deaf494f1e2c33"
            },
            {
              "version": "c0b220cf7d80eb8a36ae9f12cae6df4577a6814e",
              "status": "affected",
              "versionType": "git",
              "lessThan": "6428634f7a0b7878144b4925c37856bef3224967"
            },
            {
              "version": "c0b220cf7d80eb8a36ae9f12cae6df4577a6814e",
              "status": "affected",
              "versionType": "git",
              "lessThan": "46c3b8191aad3d032776bf3bebf03efdf5f4b905"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.3",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.3"
            },
            {
              "version": "5.10.261",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.15.212",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.178",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.145",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.97",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.18.40",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.18.*"
            },
            {
              "version": "7.1.5",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "7.1.*"
            },
            {
              "version": "7.2",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}