{
  "threat_severity" : "Moderate",
  "public_date" : "2026-04-25T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: netfilter: ip6t_eui64: reject invalid MAC header for all packets",
    "id" : "2461759",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2461759"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.1",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
    "status" : "draft"
  },
  "cwe" : "CWE-1287",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nnetfilter: ip6t_eui64: reject invalid MAC header for all packets\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.\nThe existing guard only rejects an invalid MAC header when\n`par->fragoff != 0`. For packets with `par->fragoff == 0`, `eui64_mt6()`\ncan still reach `eth_hdr(skb)` even when the MAC header is not valid.\nFix this by removing the `par->fragoff != 0` condition so that packets\nwith an invalid MAC header are rejected before accessing `eth_hdr(skb)`.", "A flaw was found in the Linux kernel's netfilter component. This vulnerability occurs because the `eui64_mt6()` function, which processes IPv6 packets, does not properly validate the MAC header for all packets. Specifically, packets with a zero fragment offset could bypass an existing guard, allowing the system to attempt to access an invalid MAC header. A remote attacker could exploit this by sending specially crafted IPv6 packets, potentially causing a system crash and leading to a Denial of Service (DoS)." ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 6",
    "fix_state" : "Under investigation",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-31685\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31685\nhttps://lore.kernel.org/linux-cve-announce/2026042545-CVE-2026-31685-3fcc@gregkh/T" ],
  "name" : "CVE-2026-31685",
  "csaw" : false
}