{"id":"CVE-2026-6426","state":"PUBLISHED","title":"Qemu-kvm: vhost inflight migration vmstate integer type mismatch causes out-of-bounds access","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.\n\nThis 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.","publishedAt":"2026-08-10T21:22:29.414Z","updatedAt":"2026-09-18T10:49:31.824Z","severity":{"score":4.4,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H","source":"redhat"},"assigner":"redhat","products":["Red Hat Red Hat Enterprise Linux 10","Red Hat Red Hat Enterprise Linux 6","Red Hat Red Hat Enterprise Linux 7","Red Hat Red Hat Enterprise Linux 8","Red Hat Red Hat Enterprise Linux 9","Red Hat Red Hat Enterprise Linux for NVIDIA 26","Red Hat Red Hat OpenShift Container Platform 4"],"affected":[{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 10","packageName":"qemu-kvm","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:10"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 6","packageName":"qemu-kvm","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:6"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 7","packageName":"qemu-kvm","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:7"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 7","packageName":"qemu-kvm-ma","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:7"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 8","packageName":"virt:rhel/qemu-kvm","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:8"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","packageName":"qemu-kvm","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:9"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux for NVIDIA 26","packageName":"qemu-kvm","defaultStatus":"unknown","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/a:redhat:enterprise_linux_nvidia:"]},{"vendor":"Red Hat","product":"Red Hat OpenShift Container Platform 4","packageName":"openshift/ose-rhel-coreos-8","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/a:redhat:openshift:4"]},{"vendor":"Red Hat","product":"Red Hat OpenShift Container Platform 4","packageName":"openshift/ose-rhel-coreos-9","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/a:redhat:openshift:4"]}],"references":["https://access.redhat.com/security/cve/CVE-2026-6426","https://bugzilla.redhat.com/show_bug.cgi?id=2513498"],"weaknesses":["CWE-681"],"ingestedAt":"2026-10-29T20:12:49.727Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/6xxx/CVE-2026-6426.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-6426","state":"PUBLISHED","datePublished":"2026-08-10T21:22:29.414Z","dateUpdated":"2026-09-18T10:49:31.824Z","assignerShortName":"redhat","assignerOrgId":"53f830b8-0a3f-465b-8143-3b8a9948e749","dateReserved":"2026-04-16T11:09:18.538Z"},"containers":{"cna":{"title":"Qemu-kvm: vhost inflight migration vmstate integer type mismatch causes out-of-bounds access","descriptions":[{"lang":"en","value":"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.\n\nThis 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."}],"affected":[{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 10","packageName":"qemu-kvm","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:10"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 6","packageName":"qemu-kvm","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:6"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 7","packageName":"qemu-kvm","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:7"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 7","packageName":"qemu-kvm-ma","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:7"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 8","packageName":"virt:rhel/qemu-kvm","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:8"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux 9","packageName":"qemu-kvm","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/o:redhat:enterprise_linux:9"]},{"vendor":"Red Hat","product":"Red Hat Enterprise Linux for NVIDIA 26","packageName":"qemu-kvm","defaultStatus":"unknown","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/a:redhat:enterprise_linux_nvidia:"]},{"vendor":"Red Hat","product":"Red Hat OpenShift Container Platform 4","packageName":"openshift/ose-rhel-coreos-8","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/a:redhat:openshift:4"]},{"vendor":"Red Hat","product":"Red Hat OpenShift Container Platform 4","packageName":"openshift/ose-rhel-coreos-9","defaultStatus":"affected","collectionURL":"https://access.redhat.com/downloads/content/package-browser/","cpes":["cpe:/a:redhat:openshift:4"]}],"references":[{"url":"https://access.redhat.com/security/cve/CVE-2026-6426","tags":["vdb-entry","x_refsource_REDHAT"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2513498","name":"RHBZ#2513498","tags":["issue-tracking","x_refsource_REDHAT"]}],"metrics":[{"other":{"content":{"value":"Low","namespace":"https://access.redhat.com/security/updates/classification/"},"type":"Red Hat severity rating"}},{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":4.4,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"HIGH","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"format":"CVSS"}],"problemTypes":[{"descriptions":[{"cweId":"CWE-681","description":"Incorrect Conversion between Numeric Types","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"redhat","orgId":"53f830b8-0a3f-465b-8143-3b8a9948e749","dateUpdated":"2026-09-18T10:49:31.824Z"},"datePublic":"2026-08-10T00:00:00.000Z","x_redhatCweChain":"CWE-681: Incorrect Conversion between Numeric Types","workarounds":[{"lang":"en","value":"If vhost inflight migration is not required, it can be disabled by omitting the inflight parameter from the vhost-user device configuration. This prevents the vulnerable VMState deserialization path from being reached on the destination.\n\nEnvironments that require vhost inflight migration for live migration of vhost-user devices cannot use this mitigation and should prioritize applying the fix."}],"timeline":[{"lang":"en","time":"2026-08-10T00:00:00.000Z","value":"Reported to Red Hat."},{"lang":"en","time":"2026-08-10T00:00:00.000Z","value":"Made public."}],"credits":[{"lang":"en","value":"Red Hat would like to thank Seungjung Kim (Kyonggi University) for reporting this issue."}],"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-11T17:41:11.267441Z","id":"CVE-2026-6426","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-11T17:51:23.060Z"}}]}}}