{
  "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-2025-21779",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2025-21779",
    "idYear": 2025,
    "status": "PUBLISHED",
    "publishedAt": "2025-02-27T02:18:23.001Z",
    "updatedAt": "2026-10-15T01:04:20.162Z",
    "importedAt": "2026-10-24T01:57:29.455Z",
    "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: Reject Hyper-V's SEND_IPI hypercalls if local APIC isn't in-kernel",
      "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nKVM: x86: Reject Hyper-V's SEND_IPI hypercalls if local APIC isn't in-kernel\n\nAdvertise support for Hyper-V's SEND_IPI and SEND_IPI_EX hypercalls if and\nonly if the local API is emulated/virtualized by KVM, and explicitly reject\nsaid hypercalls if the local APIC is emulated in userspace, i.e. don't rely\non userspace to opt-in to KVM_CAP_HYPERV_ENFORCE_CPUID.\n\nRejecting SEND_IPI and SEND_IPI_EX fixes a NULL-pointer dereference if\nHyper-V enlightenments are exposed to the guest without an in-kernel local\nAPIC:\n\n  dump_stack+0xbe/0xfd\n  __kasan_report.cold+0x34/0x84\n  kasan_report+0x3a/0x50\n  __apic_accept_irq+0x3a/0x5c0\n  kvm_hv_send_ipi.isra.0+0x34e/0x820\n  kvm_hv_hypercall+0x8d9/0x9d0\n  kvm_emulate_hypercall+0x506/0x7e0\n  __vmx_handle_exit+0x283/0xb60\n  vmx_handle_exit+0x1d/0xd0\n  vcpu_enter_guest+0x16b0/0x24c0\n  vcpu_run+0xc0/0x550\n  kvm_arch_vcpu_ioctl_run+0x170/0x6d0\n  kvm_vcpu_ioctl+0x413/0xb20\n  __se_sys_ioctl+0x111/0x160\n  do_syscal1_64+0x30/0x40\n  entry_SYSCALL_64_after_hwframe+0x67/0xd1\n\nNote, checking the sending vCPU is sufficient, as the per-VM irqchip_mode\ncan't be modified after vCPUs are created, i.e. if one vCPU has an\nin-kernel local APIC, then all vCPUs have an in-kernel local APIC.",
      "affected": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "214ff83d4473a7757fa18a64dc7efe3b0e158486",
              "status": "affected",
              "versionType": "git",
              "lessThan": "61224533f2b61e252b03e214195d27d64b22989a"
            },
            {
              "version": "214ff83d4473a7757fa18a64dc7efe3b0e158486",
              "status": "affected",
              "versionType": "git",
              "lessThan": "45fa526b0f5a34492ed0536c3cdf88b78380e4de"
            },
            {
              "version": "214ff83d4473a7757fa18a64dc7efe3b0e158486",
              "status": "affected",
              "versionType": "git",
              "lessThan": "5393cf22312418262679eaadb130d608c75fe690"
            },
            {
              "version": "214ff83d4473a7757fa18a64dc7efe3b0e158486",
              "status": "affected",
              "versionType": "git",
              "lessThan": "874ff13c73c45ecb38cb82191e8c1d523f0dc81b"
            },
            {
              "version": "214ff83d4473a7757fa18a64dc7efe3b0e158486",
              "status": "affected",
              "versionType": "git",
              "lessThan": "aca8be4403fb90db7adaf63830e27ebe787a76e8"
            },
            {
              "version": "214ff83d4473a7757fa18a64dc7efe3b0e158486",
              "status": "affected",
              "versionType": "git",
              "lessThan": "ca29f58ca374c40a0e69c5306fc5c940a0069074"
            },
            {
              "version": "214ff83d4473a7757fa18a64dc7efe3b0e158486",
              "status": "affected",
              "versionType": "git",
              "lessThan": "a8de7f100bb5989d9c3627d3a223ee1c863f3b69"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "versions": [
            {
              "version": "4.20",
              "status": "affected"
            },
            {
              "version": "0",
              "status": "unaffected",
              "versionType": "semver",
              "lessThan": "4.20"
            },
            {
              "version": "5.10.236",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.10.*"
            },
            {
              "version": "5.15.179",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "5.15.*"
            },
            {
              "version": "6.1.129",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.1.*"
            },
            {
              "version": "6.6.79",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.6.*"
            },
            {
              "version": "6.12.16",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.12.*"
            },
            {
              "version": "6.13.4",
              "status": "unaffected",
              "versionType": "semver",
              "lessThanOrEqual": "6.13.*"
            },
            {
              "version": "6.14",
              "status": "unaffected",
              "versionType": "original_commit_for_fix",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  }
}