CVE-2026-46655 (GCVE-0-2026-46655)

Vulnerability from cvelistv5 – Published: 2026-09-18 16:46 – Updated: 2026-09-23 19:15
VLAI
Title
virtio-win: Integer overflow causing a heap overflow in Viosock driver
Summary
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.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-23 19:14 UTC
CWE
  • CWE-122 - Heap-based Buffer Overflow
  • CWE-190 - Integer Overflow or Wraparound
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7620 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
virtio-win kvm-guest-drivers-windows Affected: >= mm210, < mm320
guessed Create a notification for this product.
Show details on NVD website
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