{
  "threat_severity" : "Important",
  "public_date" : "2026-06-01T12:00:00Z",
  "bugzilla" : {
    "description" : "kernel: Linux kernel: netfilter: ebtables SNAT target writes to shared memory pages during ARP hardware address rewrite",
    "id" : "2485368",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2485368"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.5",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-825",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nnetfilter: bridge: make ebt_snat ARP rewrite writable\nThe ebtables SNAT target keeps the Ethernet source address rewrite\nbehind skb_ensure_writable(skb, 0).  This is intentional: at the bridge\nebtables hooks the Ethernet header is addressed through\nskb_mac_header()/eth_hdr(), while skb->data points at the Ethernet\npayload.  Asking skb_ensure_writable() for ETH_HLEN bytes would check\nthe payload, not the Ethernet header, and would reintroduce the small\npacket regression fixed by commit 63137bc5882a.\nHowever, the optional ARP sender hardware address rewrite is different.\nIt writes through skb_store_bits() at an offset relative to skb->data:\nskb_store_bits(skb, sizeof(struct arphdr), info->mac, ETH_ALEN)\nskb_header_pointer() only safely reads the ARP header; it does not make\nthe later sender hardware address range writable.  If that range is\nstill held in a nonlinear skb fragment backed by a splice-imported file\npage, skb_store_bits() maps the frag page and copies the new MAC address\ndirectly into it.\nEnsure the ARP SHA range is writable before reading the ARP header and\nbefore calling skb_store_bits().", "A flaw was found in the Linux kernel's netfilter bridge ebtables SNAT (Source Network Address Translation) module. This vulnerability allows a local attacker on a system configured with specific bridge netfilter rules to improperly modify underlying memory pages during an ARP (Address Resolution Protocol) sender hardware address rewrite. This could lead to unintended system behavior, a denial of service, or potentially local privilege escalation, where an attacker gains higher access rights than intended." ],
  "statement" : "An Important flaw in the Linux kernel's ebtables SNAT target allows a local attacker to achieve privilege escalation, memory corruption, or denial of service. This vulnerability requires specific bridge netfilter rules to be configured, limiting its impact to systems with such specialized network configurations.",
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2026-07-14T00:00:00Z",
    "advisory" : "RHSA-2026:39082",
    "cpe" : "cpe:/a:redhat:enterprise_linux:8::nfv",
    "package" : "kernel-rt-0:4.18.0-553.143.1.rt7.484.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2026-07-14T00:00:00Z",
    "advisory" : "RHSA-2026:39083",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-553.143.1.el8_10"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2026-07-08T00:00:00Z",
    "advisory" : "RHSA-2026:36645",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-687.23.1.el9_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2026-07-08T00:00:00Z",
    "advisory" : "RHSA-2026:36645",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-687.23.1.el9_8"
  } ],
  "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" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux for NVIDIA 26",
    "fix_state" : "Will not fix",
    "package_name" : "kernel",
    "cpe" : "cpe:/a:redhat:enterprise_linux_nvidia:"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-53266\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-53266\nhttps://lore.kernel.org/linux-cve-announce/2026062517-CVE-2026-53266-6162@gregkh/T/#u" ],
  "name" : "CVE-2026-53266",
  "mitigation" : {
    "value" : "Disable ARP hardware address rewriting in ebtables SNAT rules, or remove ebtables SNAT rules that operate on ARP traffic on bridge interfaces.",
    "lang" : "en:us"
  },
  "csaw" : false
}