CVE-2026-6426Network attack vectorHinoki check available

Destination process crash via signed size conversion

Published Aug 10, 2026 · Updated Aug 10, 2026

Type mismatch in QEMU vhost inflight migration allows remote authenticated users to crash the destination QEMU process. The VMS_VBUFFER load path reads a uint64_t inflight size as int32_t, converts a negative result to size_t, and makes qemu_get_buffer() overrun its mmap-backed region. Exploitation requires control of the migration producer or write access to its channel, a little-endian destination, and configured vhost inflight migration.

CVSS severity4.4
Medium
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Type mismatch in QEMU vhost inflight migration allows remote authenticated users to crash the destination QEMU process. The VMS_VBUFFER load path reads a uint64_t inflight size as int32_t, converts a negative result to size_t, and makes qemu_get_buffer() overrun its mmap-backed region. Exploitation requires control of the migration producer or write access to its channel, a little-endian destination, and configured vhost inflight migration.

The record

CVE
CVE-2026-6426
Published
Aug 10, 2026
Updated
Aug 10, 2026
Vendor
389 Directory Server
Product
Red Hat Enterprise Linux 6
Classifications
CWE-681, T1499.004
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Aug 10, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

389 Directory Server · Red Hat Enterprise Linux 6Affected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 10Affected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 7Affected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 9Affected versions are unavailable in this record.
389 Directory Server · Red Hat OpenShift Container Platform 4Affected versions are unavailable in this record.
389 Directory Server · Red Hat Enterprise Linux 8Affected versions are unavailable in this record.

Published CVSS scores

4.4Red HatCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-681Incorrect Conversion between Numeric Types
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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