{
  "threat_severity" : "Moderate",
  "public_date" : "2025-09-18T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: wifi: brcmfmac: fix use-after-free bug in brcmf_netdev_start_xmit()",
    "id" : "2396506",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2396506"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.8",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-416",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nwifi: brcmfmac: fix use-after-free bug in brcmf_netdev_start_xmit()\n> ret = brcmf_proto_tx_queue_data(drvr, ifp->ifidx, skb);\nmay be schedule, and then complete before the line\n> ndev->stats.tx_bytes += skb->len;\n[   46.912801] ==================================================================\n[   46.920552] BUG: KASAN: use-after-free in brcmf_netdev_start_xmit+0x718/0x8c8 [brcmfmac]\n[   46.928673] Read of size 4 at addr ffffff803f5882e8 by task systemd-resolve/328\n[   46.935991]\n[   46.937514] CPU: 1 PID: 328 Comm: systemd-resolve Tainted: G           O      5.4.199-[REDACTED] #1\n[   46.947255] Hardware name: [REDACTED]\n[   46.954568] Call trace:\n[   46.957037]  dump_backtrace+0x0/0x2b8\n[   46.960719]  show_stack+0x24/0x30\n[   46.964052]  dump_stack+0x128/0x194\n[   46.967557]  print_address_description.isra.0+0x64/0x380\n[   46.972877]  __kasan_report+0x1d4/0x240\n[   46.976723]  kasan_report+0xc/0x18\n[   46.980138]  __asan_report_load4_noabort+0x18/0x20\n[   46.985027]  brcmf_netdev_start_xmit+0x718/0x8c8 [brcmfmac]\n[   46.990613]  dev_hard_start_xmit+0x1bc/0xda0\n[   46.994894]  sch_direct_xmit+0x198/0xd08\n[   46.998827]  __qdisc_run+0x37c/0x1dc0\n[   47.002500]  __dev_queue_xmit+0x1528/0x21f8\n[   47.006692]  dev_queue_xmit+0x24/0x30\n[   47.010366]  neigh_resolve_output+0x37c/0x678\n[   47.014734]  ip_finish_output2+0x598/0x2458\n[   47.018927]  __ip_finish_output+0x300/0x730\n[   47.023118]  ip_output+0x2e0/0x430\n[   47.026530]  ip_local_out+0x90/0x140\n[   47.030117]  igmpv3_sendpack+0x14c/0x228\n[   47.034049]  igmpv3_send_cr+0x384/0x6b8\n[   47.037895]  igmp_ifc_timer_expire+0x4c/0x118\n[   47.042262]  call_timer_fn+0x1cc/0xbe8\n[   47.046021]  __run_timers+0x4d8/0xb28\n[   47.049693]  run_timer_softirq+0x24/0x40\n[   47.053626]  __do_softirq+0x2c0/0x117c\n[   47.057387]  irq_exit+0x2dc/0x388\n[   47.060715]  __handle_domain_irq+0xb4/0x158\n[   47.064908]  gic_handle_irq+0x58/0xb0\n[   47.068581]  el0_irq_naked+0x50/0x5c\n[   47.072162]\n[   47.073665] Allocated by task 328:\n[   47.077083]  save_stack+0x24/0xb0\n[   47.080410]  __kasan_kmalloc.isra.0+0xc0/0xe0\n[   47.084776]  kasan_slab_alloc+0x14/0x20\n[   47.088622]  kmem_cache_alloc+0x15c/0x468\n[   47.092643]  __alloc_skb+0xa4/0x498\n[   47.096142]  igmpv3_newpack+0x158/0xd78\n[   47.099987]  add_grhead+0x210/0x288\n[   47.103485]  add_grec+0x6b0/0xb70\n[   47.106811]  igmpv3_send_cr+0x2e0/0x6b8\n[   47.110657]  igmp_ifc_timer_expire+0x4c/0x118\n[   47.115027]  call_timer_fn+0x1cc/0xbe8\n[   47.118785]  __run_timers+0x4d8/0xb28\n[   47.122457]  run_timer_softirq+0x24/0x40\n[   47.126389]  __do_softirq+0x2c0/0x117c\n[   47.130142]\n[   47.131643] Freed by task 180:\n[   47.134712]  save_stack+0x24/0xb0\n[   47.138041]  __kasan_slab_free+0x108/0x180\n[   47.142146]  kasan_slab_free+0x10/0x18\n[   47.145904]  slab_free_freelist_hook+0xa4/0x1b0\n[   47.150444]  kmem_cache_free+0x8c/0x528\n[   47.154292]  kfree_skbmem+0x94/0x108\n[   47.157880]  consume_skb+0x10c/0x5a8\n[   47.161466]  __dev_kfree_skb_any+0x88/0xa0\n[   47.165598]  brcmu_pkt_buf_free_skb+0x44/0x68 [brcmutil]\n[   47.171023]  brcmf_txfinalize+0xec/0x190 [brcmfmac]\n[   47.176016]  brcmf_proto_bcdc_txcomplete+0x1c0/0x210 [brcmfmac]\n[   47.182056]  brcmf_sdio_sendfromq+0x8dc/0x1e80 [brcmfmac]\n[   47.187568]  brcmf_sdio_dpc+0xb48/0x2108 [brcmfmac]\n[   47.192529]  brcmf_sdio_dataworker+0xc8/0x238 [brcmfmac]\n[   47.197859]  process_one_work+0x7fc/0x1a80\n[   47.201965]  worker_thread+0x31c/0xc40\n[   47.205726]  kthread+0x2d8/0x370\n[   47.208967]  ret_from_fork+0x10/0x18\n[   47.212546]\n[   47.214051] The buggy address belongs to the object at ffffff803f588280\n[   47.214051]  which belongs to the cache skbuff_head_cache of size 208\n[   47.227086] The buggy address is located 104 bytes inside of\n[   47.227086]  208-byte region [ffffff803f588280, ffffff803f588350)\n[   47.238814] The buggy address belongs to the page:\n[   47.243618] page:ffffffff00dd6200 refcount:1 mapcou\n---truncated---", "A use after free exists in the wifi module of the linux kernel in the function brcmf_netdev_start_xmit(),thereby leading to damage to system availability and integrity." ],
  "statement" : "A Use-After-Free vulnerability was found in brcmf_netdev_start_xmit() in the Broadcom brcmfmac driver.\nThe function updated ndev->stats.tx_bytes after calling brcmf_proto_tx_queue_data(), which may complete asynchronously and free the skb object before accessing it.\nThe patch stores skb->len in a local variable before the transmission call to prevent dereferencing freed memory.\nPrivilege required is low (PR:L) since the issue is triggered during normal packet transmission from a network interface, accessible to local processes using networking APIs.",
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 7 Extended Lifecycle Support",
    "release_date" : "2025-12-09T00:00:00Z",
    "advisory" : "RHSA-2025:22914",
    "cpe" : "cpe:/a:redhat:rhel_extras_rt_els:7",
    "package" : "kernel-rt-0:3.10.0-1160.143.1.rt56.1295.el7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7 Extended Lifecycle Support",
    "release_date" : "2025-12-09T00:00:00Z",
    "advisory" : "RHSA-2025:22910",
    "cpe" : "cpe:/o:redhat:rhel_els:7",
    "package" : "kernel-0:3.10.0-1160.143.1.el7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2023-05-16T00:00:00Z",
    "advisory" : "RHSA-2023:2951",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-477.10.1.el8_8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.2 Advanced Update Support",
    "release_date" : "2025-12-17T00:00:00Z",
    "advisory" : "RHSA-2025:23445",
    "cpe" : "cpe:/o:redhat:rhel_aus:8.2",
    "package" : "kernel-0:4.18.0-193.178.1.el8_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support",
    "release_date" : "2025-12-04T00:00:00Z",
    "advisory" : "RHSA-2025:22752",
    "cpe" : "cpe:/o:redhat:rhel_aus:8.4",
    "package" : "kernel-0:4.18.0-305.179.1.el8_4"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On",
    "release_date" : "2025-12-04T00:00:00Z",
    "advisory" : "RHSA-2025:22752",
    "cpe" : "cpe:/o:redhat:rhel_eus_long_life:8.4",
    "package" : "kernel-0:4.18.0-305.179.1.el8_4"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support",
    "release_date" : "2025-11-12T00:00:00Z",
    "advisory" : "RHSA-2025:21084",
    "cpe" : "cpe:/o:redhat:rhel_aus:8.6",
    "package" : "kernel-0:4.18.0-372.168.1.el8_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.6 Telecommunications Update Service",
    "release_date" : "2025-11-12T00:00:00Z",
    "advisory" : "RHSA-2025:21084",
    "cpe" : "cpe:/o:redhat:rhel_tus:8.6",
    "package" : "kernel-0:4.18.0-372.168.1.el8_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions",
    "release_date" : "2025-11-12T00:00:00Z",
    "advisory" : "RHSA-2025:21084",
    "cpe" : "cpe:/o:redhat:rhel_e4s:8.6",
    "package" : "kernel-0:4.18.0-372.168.1.el8_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2023-05-09T00:00:00Z",
    "advisory" : "RHSA-2023:2458",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-284.11.1.el9_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2023-05-09T00:00:00Z",
    "advisory" : "RHSA-2023:2458",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-284.11.1.el9_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions",
    "release_date" : "2025-11-12T00:00:00Z",
    "advisory" : "RHSA-2025:21091",
    "cpe" : "cpe:/a:redhat:rhel_e4s:9.0",
    "package" : "kernel-0:5.14.0-70.153.1.el9_0"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions",
    "release_date" : "2025-11-12T00:00:00Z",
    "advisory" : "RHSA-2025:21136",
    "cpe" : "cpe:/a:redhat:rhel_e4s:9.0::nfv",
    "package" : "kernel-rt-0:5.14.0-70.153.1.rt21.225.el9_0"
  } ],
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Not 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 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-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2022-50408\nhttps://nvd.nist.gov/vuln/detail/CVE-2022-50408\nhttps://lore.kernel.org/linux-cve-announce/2025091853-CVE-2022-50408-5835@gregkh/T" ],
  "name" : "CVE-2022-50408",
  "mitigation" : {
    "value" : "To mitigate this issue, prevent module brcmfmac from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.",
    "lang" : "en:us"
  },
  "csaw" : false
}