netfilter: ip6t_eui64: reject invalid MAC header for all packets_CVE-2026-31685

{
    "lastseen": "",
    "description": "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->fragoff != 0`. For packets with `par->fragoff == 0`, `eui64_mt6()`\ncan still reach `eth_hdr(skb)` even when the MAC header is not valid.\n\nFix this by removing the `par->fragoff != 0` condition so that packets\nwith an invalid MAC header are rejected before accessing `eth_hdr(skb)`.",
    "published": "2026-04-25T08:47:02.857Z",
    "modified": "2026-04-27T14:05:04.347Z",
    "type": "cve",
    "title": "netfilter: ip6t_eui64: reject invalid MAC header for all packets",
    "source": "Linux",
    "references": "https://git.kernel.org/stable/c/288138418bef956f8b295751a4536c60f0e89f4a\nhttps://git.kernel.org/stable/c/9eda5478746ef7dc0e4e537b5a5e4b0ca1027091\nhttps://git.kernel.org/stable/c/807d6ee15804df6f01a35c910f09612e858739a6\nhttps://git.kernel.org/stable/c/309ae3e9a51a69699ca94eac5fac5688fa562d55\nhttps://git.kernel.org/stable/c/fdce0b3590f724540795b874b4c8850c90e6b0a8",
    "id": "CVE-2026-31685",
    "bulletinFamily": "",
    "cwe": null,
    "cvelist": null,
    "sourceData": "Linux Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\nLinux Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\nLinux Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\nLinux Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\nLinux Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\nLinux Linux 2.6.12",
    "sourceHref": "",
    "cvss": {
        "score": 9.4,
        "severity": "CRITICAL",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:H",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "Linux",
    "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
    "vendor": "Linux",
    "ai_description": "A vulnerability in the Linux kernel's netfilter: ip6t_eui64 module allows an attacker to reject invalid MAC headers for all packets, potentially leading to a denial of service.",
    "ai_severity": "Critical",
    "ai_vendor": "Linux",
    "ai_product": "Linux Kernel",
    "ai_version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, 2.6.12",
    "ai_score": 9.4
}