{
  "threat_severity" : "Moderate",
  "public_date" : "2026-05-01T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: io_uring/rsrc: reject zero-length fixed buffer import",
    "id" : "2464402",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2464402"
  },
  "cvss3" : {
    "cvss3_base_score" : "7.1",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
    "status" : "verified"
  },
  "cwe" : "CWE-805",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nio_uring/rsrc: reject zero-length fixed buffer import\nvalidate_fixed_range() admits buf_addr at the exact end of the\nregistered region when len is zero, because the check uses strict\ngreater-than (buf_end > imu->ubuf + imu->len).  io_import_fixed()\nthen computes offset == imu->len, which causes the bvec skip logic\nto advance past the last bio_vec entry and read bv_offset from\nout-of-bounds slab memory.\nReturn early from io_import_fixed() when len is zero.  A zero-length\nimport has no data to transfer and should not walk the bvec array\nat all.\nBUG: KASAN: slab-out-of-bounds in io_import_reg_buf+0x697/0x7f0\nRead of size 4 at addr ffff888002bcc254 by task poc/103\nCall Trace:\nio_import_reg_buf+0x697/0x7f0\nio_write_fixed+0xd9/0x250\n__io_issue_sqe+0xad/0x710\nio_issue_sqe+0x7d/0x1100\nio_submit_sqes+0x86a/0x23c0\n__do_sys_io_uring_enter+0xa98/0x1590\nAllocated by task 103:\nThe buggy address is located 12 bytes to the right of\nallocated 584-byte region [ffff888002bcc000, ffff888002bcc248)", "A flaw was found in the Linux kernel's io_uring subsystem. A local attacker can exploit a vulnerability in the `io_import_fixed()` function by importing a zero-length fixed buffer. This can lead to an out-of-bounds read from slab memory, potentially resulting in information disclosure or a denial of service." ],
  "affected_release" : [ {
    "product_name" : "Red Hat Enterprise Linux 10",
    "release_date" : "2026-05-28T00:00:00Z",
    "advisory" : "RHSA-2026:21557",
    "cpe" : "cpe:/o:redhat:enterprise_linux:10.2",
    "package" : "kernel-0:6.12.0-211.18.1.el10_2"
  } ],
  "package_state" : [ {
    "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" : "Not affected",
    "package_name" : "kernel",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  }, {
    "product_name" : "Red Hat Enterprise Linux 9",
    "fix_state" : "Not affected",
    "package_name" : "kernel-rt",
    "cpe" : "cpe:/o:redhat:enterprise_linux:9"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-43006\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-43006\nhttps://lore.kernel.org/linux-cve-announce/2026050153-CVE-2026-43006-e4be@gregkh/T" ],
  "name" : "CVE-2026-43006",
  "csaw" : false
}