{
  "threat_severity" : "Moderate",
  "public_date" : "2025-10-04T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: null_blk: Always check queue mode setting from configfs",
    "id" : "2401524",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2401524"
  },
  "cvss3" : {
    "cvss3_base_score" : "5.5",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-1288",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nnull_blk: Always check queue mode setting from configfs\nMake sure to check device queue mode in the null_validate_conf() and\nreturn error for NULL_Q_RQ as we don't allow legacy I/O path, without\nthis patch we get OOPs when queue mode is set to 1 from configfs,\nfollowing are repro steps :-\nmodprobe null_blk nr_devices=0\nmkdir config/nullb/nullb0\necho 1 > config/nullb/nullb0/memory_backed\necho 4096 > config/nullb/nullb0/blocksize\necho 20480 > config/nullb/nullb0/size\necho 1 > config/nullb/nullb0/queue_mode\necho 1 > config/nullb/nullb0/power\nEntering kdb (current=0xffff88810acdd080, pid 2372) on processor 42 Oops: (null)\ndue to oops @ 0xffffffffc041c329\nCPU: 42 PID: 2372 Comm: sh Tainted: G           O     N 6.3.0-rc5lblk+ #5\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014\nRIP: 0010:null_add_dev.part.0+0xd9/0x720 [null_blk]\nCode: 01 00 00 85 d2 0f 85 a1 03 00 00 48 83 bb 08 01 00 00 00 0f 85 f7 03 00 00 80 bb 62 01 00 00 00 48 8b 75 20 0f 85 6d 02 00 00 <48> 89 6e 60 48 8b 75 20 bf 06 00 00 00 e8 f5 37 2c c1 48 8b 75 20\nRSP: 0018:ffffc900052cbde0 EFLAGS: 00010246\nRAX: 0000000000000001 RBX: ffff88811084d800 RCX: 0000000000000001\nRDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888100042e00\nRBP: ffff8881053d8200 R08: ffffc900052cbd68 R09: ffff888105db2000\nR10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000002\nR13: ffff888104765200 R14: ffff88810eec1748 R15: ffff88810eec1740\nFS:  00007fd445fd1740(0000) GS:ffff8897dfc80000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 0000000000000060 CR3: 0000000166a00000 CR4: 0000000000350ee0\nDR0: ffffffff8437a488 DR1: ffffffff8437a489 DR2: ffffffff8437a48a\nDR3: ffffffff8437a48b DR6: 00000000ffff0ff0 DR7: 0000000000000400\nCall Trace:\n<TASK>\nnullb_device_power_store+0xd1/0x120 [null_blk]\nconfigfs_write_iter+0xb4/0x120\nvfs_write+0x2ba/0x3c0\nksys_write+0x5f/0xe0\ndo_syscall_64+0x3b/0x90\nentry_SYSCALL_64_after_hwframe+0x72/0xdc\nRIP: 0033:0x7fd4460c57a7\nCode: 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24\nRSP: 002b:00007ffd3792a4a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001\nRAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fd4460c57a7\nRDX: 0000000000000002 RSI: 000055b43c02e4c0 RDI: 0000000000000001\nRBP: 000055b43c02e4c0 R08: 000000000000000a R09: 00007fd44615b4e0\nR10: 00007fd44615b3e0 R11: 0000000000000246 R12: 0000000000000002\nR13: 00007fd446198520 R14: 0000000000000002 R15: 00007fd446198700\n</TASK>", "A missing validation flaw was found in the Linux kernel null_blk driver's configuration handling. A local user with access to configfs can configure a null_blk device with queue_mode set to 1 (legacy I/O path), which is no longer supported, causing the driver to proceed without proper validation and triggering a kernel oops and denial of service through system crash." ],
  "statement" : "The null_validate_conf() function fails to check the device queue mode setting when configured via configfs. When userspace sets queue_mode to 1 (NULL_Q_RQ, representing the legacy request-based I/O path), the driver should reject this configuration since the legacy path has been removed. Instead, the driver accepts the invalid mode and attempts to initialize with it, causing a kernel oops when the incompatible code paths execute.",
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 8",
    "release_date" : "2024-05-22T00:00:00Z",
    "advisory" : "RHSA-2024:3138",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8",
    "package" : "kernel-0:4.18.0-553.el8_10"
  }, {
    "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" : "2023-11-07T00:00:00Z",
    "advisory" : "RHSA-2023:6583",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9",
    "package" : "kernel-0:5.14.0-362.8.1.el9_3"
  } ],
  "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" : "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" : "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-2023-53576\nhttps://nvd.nist.gov/vuln/detail/CVE-2023-53576\nhttps://lore.kernel.org/linux-cve-announce/2025100454-CVE-2023-53576-c5dd@gregkh/T" ],
  "name" : "CVE-2023-53576",
  "mitigation" : {
    "value" : "To mitigate this issue, prevent the null_blk module from loading. See https://access.redhat.com/solutions/41278 for instructions on blacklisting kernel modules.",
    "lang" : "en:us"
  },
  "csaw" : false
}