Vulnerability Description
A type mismatch vulnerability was found in QEMU's vhost inflight migration VMState handling. The destination buffer size is stored as a uint64_t but read by the VMS_VBUFFER load path as a signed int32_t. On little-endian hosts, a crafted incoming migration state with bit 31 set causes the value to be interpreted as negative and then implicitly converted to a very large size_t, leading qemu_get_buffer() to copy migration-stream data beyond the bounds of the mmap-backed inflight region. This can result in a crash of the QEMU process or memory corruption. Exploitation requires control of the migration producer or write access to the migration channel, combined with a destination configured to use vhost inflight migration.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://access.redhat.com/security/cve/CVE-2026-6426
- https://bugzilla.redhat.com/show_bug.cgi?id=2513498
FAQ
What is CVE-2026-6426?
CVE-2026-6426 is a vulnerability with a CVSS score of 4.4 (MEDIUM). A type mismatch vulnerability was found in QEMU's vhost inflight migration VMState handling. The destination buffer size is stored as a uint64_t but read by the VMS_VBUFFER load path as a signed int32...
How severe is CVE-2026-6426?
CVE-2026-6426 has been rated MEDIUM with a CVSS base score of 4.4/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-6426?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.