{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-46655", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-05-15T20:11:54.585Z", "datePublished": "2026-09-18T16:46:34.832Z", "dateUpdated": "2026-09-18T16:46:50.352Z"}, "containers": {"cna": {"title": "virtio-win: Integer overflow causing a heap overflow in Viosock driver", "problemTypes": [{"descriptions": [{"cweId": "CWE-122", "lang": "en", "description": "CWE-122: Heap-based Buffer Overflow", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-190", "lang": "en", "description": "CWE-190: Integer Overflow or Wraparound", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}}], "references": [{"name": "https://github.com/virtio-win/kvm-guest-drivers-windows/security/advisories/GHSA-qrhp-4mhp-hjwh", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/virtio-win/kvm-guest-drivers-windows/security/advisories/GHSA-qrhp-4mhp-hjwh"}, {"name": "https://github.com/virtio-win/kvm-guest-drivers-windows/pull/1568", "tags": ["x_refsource_MISC"], "url": "https://github.com/virtio-win/kvm-guest-drivers-windows/pull/1568"}, {"name": "https://github.com/virtio-win/kvm-guest-drivers-windows/commit/c6bef93d7909584bbda4e5c87603ea175825f342", "tags": ["x_refsource_MISC"], "url": "https://github.com/virtio-win/kvm-guest-drivers-windows/commit/c6bef93d7909584bbda4e5c87603ea175825f342"}, {"name": "https://github.com/virtio-win/kvm-guest-drivers-windows/releases/tag/mm320", "tags": ["x_refsource_MISC"], "url": "https://github.com/virtio-win/kvm-guest-drivers-windows/releases/tag/mm320"}], "affected": [{"vendor": "virtio-win", "product": "kvm-guest-drivers-windows", "versions": [{"version": ">= mm210, < mm320", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-09-18T16:46:50.352Z"}, "descriptions": [{"lang": "en", "value": "virtio-win provides Windows paravirtualized drivers for QEMU and KVM. From mm210 until mm320, the Viosock driver permits a low-privilege local process to submit an IOCTL_SELECT request with attacker-controlled VIRTIO_VSOCK_SELECT.Fdss[*].fd_count values that overflow the 32-bit sum used by VIOSockSelect for bounds checking. The wrapped sum can pass the FD_SETSIZE check even though an individual descriptor count is much larger than the expected limit. VIOSockSelectCopyFds then iterates using the unchecked count and writes beyond the allocated pPkt->Fds array in the NonPagedPool kernel heap. Successful exploitation can corrupt kernel memory and enable privilege escalation in a Windows guest running the driver. This issue is fixed in mm320."}], "source": {"advisory": "GHSA-qrhp-4mhp-hjwh", "discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"product": "kvm-guest-drivers-windows", "vendor": "virtio-win", "versions": [{"status": "affected", "version": ">= mm210, < mm320"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "virtio-win provides Windows paravirtualized drivers for QEMU and KVM. From mm210 until mm320, the Viosock driver permits a low-privilege local process to submit an IOCTL_SELECT request with attacker-controlled VIRTIO_VSOCK_SELECT.Fdss[*].fd_count values that overflow the 32-bit sum used by VIOSockSelect for bounds checking. The wrapped sum can pass the FD_SETSIZE check even though an individual descriptor count is much larger than the expected limit. VIOSockSelectCopyFds then iterates using the unchecked count and writes beyond the allocated pPkt->Fds array in the NonPagedPool kernel heap. Successful exploitation can corrupt kernel memory and enable privilege escalation in a Windows guest running the driver. This issue is fixed in mm320."}], "id": "CVE-2026-46655", "lastModified": "2026-09-18T17:16:57.373", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 7.8, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 5.9, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-09-18T17:16:57.373", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/virtio-win/kvm-guest-drivers-windows/commit/c6bef93d7909584bbda4e5c87603ea175825f342"}, {"source": "security-advisories@github.com", "url": "https://github.com/virtio-win/kvm-guest-drivers-windows/pull/1568"}, {"source": "security-advisories@github.com", "url": "https://github.com/virtio-win/kvm-guest-drivers-windows/releases/tag/mm320"}, {"source": "security-advisories@github.com", "url": "https://github.com/virtio-win/kvm-guest-drivers-windows/security/advisories/GHSA-qrhp-4mhp-hjwh"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-122"}, {"lang": "en", "value": "CWE-190"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{"bugzilla": {"description": "virtio-win: viosock.sys: integer overflow in VIOSockSelect leads to heap-based buffer overflow", "id": "2489170", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2489170"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.8", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-190", "details": ["A flaw was found in virtio-win. A low-integrity process can issue an IOCTL request to viosock.sys!VIOSockSelect with a maliciously crafted request that causes an integer overflow. This allows the process to circumvent bounds checking, resulting in a heap overflow in the NonPagedPool kernel heap. The flaw could be exploited to escalate privileges on Windows systems running this driver."], "name": "CVE-2026-46655", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "virtio-win", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "virtio-win", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "virtio-win", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:container_native_virtualization:4", "fix_state": "Affected", "package_name": "container-native-virtualization/virtio-win", "product_name": "Red Hat OpenShift Virtualization 4"}], "public_date": "2026-06-16T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-46655\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-46655\nhttps://github.com/virtio-win/kvm-guest-drivers-windows/security/advisories/GHSA-qrhp-4mhp-hjwh"], "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": null}], "enrichment": {"confidence": 100.0, "confidence_source": "manual", "scores": [{"score": 100.0, "source": "manual"}]}, "product": "kvm-guest-drivers-windows", "vendor": "virtio-win"}], "created": "2026-06-17T18:15:10.531251+00:00", "updated": "2026-06-24T16:04:10.377934+00:00", "vendors": ["virtio-win", "virtio-win$PRODUCT$kvm-guest-drivers-windows"]}