Multiple vulnerabilities in bhyve device models
FreeBSD-SA-26:72.bhyve · CVE-2026-101309, CVE-2026-101310, CVE-2026-101311
Our decision for FreeSense
The bhyve hypervisor userland is not built into FreeSense.
- freesense-os-base patches/0003-release-and-src-conf.patch: WITHOUT_BHYVE=YES
By FreeSense version
| Version | Status | FreeBSD pin |
|---|---|---|
| FreeSense 1.01.0.7 · frozen, no further fixes | Not relevant | 2026-08-03e004ff15 |
| FreeSense 1.11.1.9 | Not relevant | 2026-10-04a52c50b4 |
| FreeSense 1.21.2.0-DEVELOPMENT | Not relevant | 2026-10-04a52c50b4 |
Workaround
No workaround is available. Virtual machines that provide none of the "xhci", "hda", and "fbuf" devices to guests are not affected.
What FreeBSD says
Several vulnerabilities were found in the bhyve hypervisor's device models. 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. (CVE-2026-101309) The HDA audio device model did not check for zero-length Buffer Descriptor List (BDL) entries when starting a stream. A zero-length entry caused an out-of-bounds read or write during DMA transfer processing. BDL fields were also subject to modification by the guest after validation. (CVE-2026-101310) The framebuffer device model's maximum resolution constants were duplicated between the framebuffer and RFB modules and had gotten out of sync. Additio
Impact
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.
Excerpt from the FreeBSD advisory. Read the original for the full text and the fix.