{
  "threat_severity" : "Moderate",
  "public_date" : "2026-04-20T00:00:00Z",
  "bugzilla" : {
    "description" : "kernel: X.509: Fix out-of-bounds access when parsing extensions",
    "id" : "2459691",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=2459691"
  },
  "cvss3" : {
    "cvss3_base_score" : "6.6",
    "cvss3_scoring_vector" : "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L",
    "status" : "draft"
  },
  "cwe" : "CWE-125",
  "details" : [ "In the Linux kernel, the following vulnerability has been resolved:\nX.509: Fix out-of-bounds access when parsing extensions\nLeo reports an out-of-bounds access when parsing a certificate with\nempty Basic Constraints or Key Usage extension because the first byte of\nthe extension is read before checking its length.  Fix it.\nThe bug can be triggered by an unprivileged user by submitting a\nspecially crafted certificate to the kernel through the keyrings(7) API.\nLeo has demonstrated this with a proof-of-concept program responsibly\ndisclosed off-list.", "A flaw was found in the Linux kernel. An unprivileged user can exploit this vulnerability by submitting a specially crafted X.509 certificate to the kernel through the keyrings(7) application programming interface (API). This certificate, specifically when containing empty Basic Constraints or Key Usage extensions, can trigger an out-of-bounds access during parsing. An out-of-bounds access is a memory corruption issue where a program attempts to read or write data beyond the allocated memory region, which can lead to system instability or a denial of service." ],
  "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"
  } ],
  "references" : [ "https://www.cve.org/CVERecord?id=CVE-2026-31430\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-31430\nhttps://lore.kernel.org/linux-cve-announce/2026042008-CVE-2026-31430-299d@gregkh/T" ],
  "name" : "CVE-2026-31430",
  "csaw" : false
}