{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2021-47390",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-47390",
    "idYear": 2021,
    "status": "PUBLISHED",
    "publishedAt": "2024-05-21T15:03:48.883Z",
    "updatedAt": "2026-08-05T08:47:35.643Z",
    "importedAt": "2026-10-24T01:56:36.661Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "KVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86: Fix stack-out-of-bounds memory access from ioapic_write_indirect()\n\nKASAN reports the following issue:\n\n BUG: KASAN: stack-out-of-bounds in kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n Read of size 8 at addr ffffc9001364f638 by task qemu-kvm/4798\n\n CPU: 0 PID: 4798 Comm: qemu-kvm Tainted: G               X --------- ---\n Hardware name: AMD Corporation DAYTONA_X/DAYTONA_X, BIOS RYM0081C 07/13/2020\n Call Trace:\n  dump_stack+0xa5/0xe6\n  print_address_description.constprop.0+0x18/0x130\n  ? kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n  __kasan_report.cold+0x7f/0x114\n  ? kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n  kasan_report+0x38/0x50\n  kasan_check_range+0xf5/0x1d0\n  kvm_make_vcpus_request_mask+0x174/0x440 [kvm]\n  kvm_make_scan_ioapic_request_mask+0x84/0xc0 [kvm]\n  ? kvm_arch_exit+0x110/0x110 [kvm]\n  ? sched_clock+0x5/0x10\n  ioapic_write_indirect+0x59f/0x9e0 [kvm]\n  ? static_obj+0xc0/0xc0\n  ? __lock_acquired+0x1d2/0x8c0\n  ? kvm_ioapic_eoi_inject_work+0x120/0x120 [kvm]\n\nThe problem appears to be that 'vcpu_bitmap' is allocated as a single long\non stack and it should really be KVM_MAX_VCPUS long. We also seem to clear\nthe lower 16 bits of it with bitmap_zero() for no particular reason (my\nguess would be that 'bitmap' and 'vcpu_bitmap' variables in\nkvm_bitmap_or_dest_vcpus() caused the confusion: while the later is indeed\n16-bit long, the later should accommodate all possible vCPUs).",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "7ee30bc132c683d06a6d9e360e39e483e3990708",
              "status": "affected",
              "versionType": "git",
              "lessThan": "bebabb76ad9acca8858e0371e102fb60d708e25b"
            },
            {
              "version": "7ee30bc132c683d06a6d9e360e39e483e3990708",
              "status": "affected",
              "versionType": "git",
              "lessThan": "99a9e9b80f19fc63be005a33d76211dd23114792"
            },
            {
              "version": "7ee30bc132c683d06a6d9e360e39e483e3990708",
              "status": "affected",
              "versionType": "git",
              "lessThan": "2f9b68f57c6278c322793a06063181deded0ad69"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "5.5",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "5.5"
            },
            {
              "version": "5.10.71",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.14.10",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.14.*"
            },
            {
              "version": "5.15",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}