{
  "threat_severity" : "Moderate",
  "public_date" : "2026-06-24T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: netfilter: nf_log: validate MAC header was set before dumping it",
    "id" : "2492091",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2492091"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.0",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
    "status" : "draft"
  },
  "cwe" : "CWE-125",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nnetfilter: nf_log: validate MAC header was set before dumping it\nThe fallback path of dump_mac_header() guards the MAC header access\nonly with \"skb->mac_header != skb->network_header\", without checking\nskb_mac_header_was_set(). When the MAC header is unset, mac_header is\n0xffff, so the test passes and skb_mac_header(skb) returns\nskb->head + 0xffff, ~64 KiB past the buffer; the loop then reads\ndev->hard_header_len bytes out of bounds into the kernel log.\nThis is reachable via the netdev logger: nf_log_unknown_packet() calls\ndump_mac_header() unconditionally, and an skb sent through AF_PACKET\nwith PACKET_QDISC_BYPASS reaches the egress hook with mac_header still\nunset (__dev_queue_xmit(), which would reset it, is bypassed).\nAdd the skb_mac_header_was_set() check the ARPHRD_ETHER path already\nuses, and replace the open-coded MAC header length test with\nskb_mac_header_len(). Only skbs with an unset MAC header are affected;\nvalid ones are dumped as before.\nBUG: KASAN: slab-out-of-bounds in dump_mac_header (net/netfilter/nf_log_syslog.c:831)\nRead of size 1 at addr ffff88800ea49d3f by task exploit/148\nCall Trace:\nkasan_report (mm/kasan/report.c:595)\ndump_mac_header (net/netfilter/nf_log_syslog.c:831)\nnf_log_netdev_packet (net/netfilter/nf_log_syslog.c:938 net/netfilter/nf_log_syslog.c:963)\nnf_log_packet (net/netfilter/nf_log.c:260)\nnft_log_eval (net/netfilter/nft_log.c:60)\nnft_do_chain (net/netfilter/nf_tables_core.c:285)\nnft_do_chain_netdev (net/netfilter/nft_chain_filter.c:307)\nnf_hook_slow (net/netfilter/core.c:619)\nnf_hook_direct_egress (net/packet/af_packet.c:257)\npacket_xmit (net/packet/af_packet.c:280)\npacket_sendmsg (net/packet/af_packet.c:3114)\n__sys_sendto (net/socket.c:2265)", "A flaw was found in the Linux kernel's netfilter logging component. This vulnerability occurs because the system does not properly check if a network packet's Media Access Control (MAC) header is valid before attempting to log it. A local attacker could send a specially crafted network packet, leading to an out-of-bounds read. This could result in the disclosure of sensitive information from kernel memory or cause a system crash, leading to a denial of service." ],
  "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 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-2026-52942\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-52942\nhttps://lore.kernel.org/linux-cve-announce/2026062435-CVE-2026-52942-2530@gregkh/T" ],
  "name" : "CVE-2026-52942",
  "csaw" : false
}