{
  "threat_severity" : "Moderate",
  "public_date" : "2025-12-08T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: exfat: validate cluster allocation bits of the allocation bitmap",
    "id" : "2419844",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2419844"
  },
  "cvss3" : {
    "cvss3_base_score" : "6.3",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H",
    "status" : "draft"
  },
  "cwe" : "CWE-1285",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nexfat: validate cluster allocation bits of the allocation bitmap\nsyzbot created an exfat image with cluster bits not set for the allocation\nbitmap. exfat-fs reads and uses the allocation bitmap without checking\nthis. The problem is that if the start cluster of the allocation bitmap\nis 6, cluster 6 can be allocated when creating a directory with mkdir.\nexfat zeros out this cluster in exfat_mkdir, which can delete existing\nentries. This can reallocate the allocated entries. In addition,\nthe allocation bitmap is also zeroed out, so cluster 6 can be reallocated.\nThis patch adds exfat_test_bitmap_range to validate that clusters used for\nthe allocation bitmap are correctly marked as in-use." ],
  "statement" : "This vulnerability is rated Moderate for Red Hat Enterprise Linux 9 and 10. An attacker could craft a malicious exFAT image that, when mounted and a directory created, could lead to data corruption or a denial of service. Red Hat Enterprise Linux 6, 7, and 8 are not affected as the vulnerable code is not present.",
  "package_state" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "fix_state" : "Fix deferred",
    "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" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:8"
  }, {
    "product_name" : "Red Hat Enterprise Linux 8",
    "fix_state" : "Not affected",
    "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",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Fix deferred",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat In-Vehicle Operating System 1",
    "fix_state" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:rhivos:1"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2025-40307\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-40307\nhttps://lore.kernel.org/linux-cve-announce/2025120820-CVE-2025-40307-40f1@gregkh/T" ],
  "name" : "CVE-2025-40307",
  "csaw" : false
}