CVE-2026-101309

The xHCI (USB 3) device model did not validate or save the event ring size provided by the guest. The size was re-read from guest memory on each use, and Transfer Request Block (TRB) fields were loaded without protection against concurrent modification by the guest. This race condition could be triggered by a guest running malicious, privileged code. A malicious guest can crash the bhyve process or potentially execute arbitrary code in the host userspace context running the virtual machine, subject to bhyve's Capsicum sandbox.

CVSS v3 7.0 HIGH

7.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.0 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://security.freebsd.org/advisories/FreeBSD-SA-26:72.bhyve.asc

Configurations

No configuration.

History

15 Oct 2026, 16:17

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.0

15 Oct 2026, 08:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-15 08:16

Updated : 2026-10-16 04:18

NVD link : CVE-2026-101309

Mitre link : CVE-2026-101309

CVE.ORG link : CVE-2026-101309

JSON object : View

Products Affected

No product.

CWE

CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

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