{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2"
            },
            {
              "fixed": "4d75bc2cd093bf5803edf512c099bfb220fd6459"
            },
            {
              "fixed": "7d6a57411caf54df025860c9b1a82cd42d57a562"
            },
            {
              "fixed": "d5603591373441fecf9951833d6d873e09320f08"
            },
            {
              "fixed": "288138418bef956f8b295751a4536c60f0e89f4a"
            },
            {
              "fixed": "9eda5478746ef7dc0e4e537b5a5e4b0ca1027091"
            },
            {
              "fixed": "807d6ee15804df6f01a35c910f09612e858739a6"
            },
            {
              "fixed": "309ae3e9a51a69699ca94eac5fac5688fa562d55"
            },
            {
              "fixed": "fdce0b3590f724540795b874b4c8850c90e6b0a8"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.6.12"
            },
            {
              "fixed": "5.10.258"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.11.0"
            },
            {
              "fixed": "5.15.209"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "5.16.0"
            },
            {
              "fixed": "6.1.175"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.2.0"
            },
            {
              "fixed": "6.6.136"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.12.83"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.24"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "6.19.14"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31685.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ip6t_eui64: reject invalid MAC header for all packets\n\n`eui64_mt6()` derives a modified EUI-64 from the Ethernet source address\nand compares it with the low 64 bits of the IPv6 source address.\n\nThe existing guard only rejects an invalid MAC header when\n`par-\u003efragoff != 0`. For packets with `par-\u003efragoff == 0`, `eui64_mt6()`\ncan still reach `eth_hdr(skb)` even when the MAC header is not valid.\n\nFix this by removing the `par-\u003efragoff != 0` condition so that packets\nwith an invalid MAC header are rejected before accessing `eth_hdr(skb)`.",
  "id": "CVE-2026-31685",
  "modified": "2026-07-08T05:37:12.866892107Z",
  "published": "2026-04-25T08:47:02.857Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/288138418bef956f8b295751a4536c60f0e89f4a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/309ae3e9a51a69699ca94eac5fac5688fa562d55"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4d75bc2cd093bf5803edf512c099bfb220fd6459"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7d6a57411caf54df025860c9b1a82cd42d57a562"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/807d6ee15804df6f01a35c910f09612e858739a6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9eda5478746ef7dc0e4e537b5a5e4b0ca1027091"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d5603591373441fecf9951833d6d873e09320f08"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fdce0b3590f724540795b874b4c8850c90e6b0a8"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31685.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31685"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.7.5",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "netfilter: ip6t_eui64: reject invalid MAC header for all packets"
}