What happened
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. 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.
Affected versions
FreeBSD: 15.1-RELEASE through before p5 (release); 14.5-RELEASE through before p2 (release); 14.4-RELEASE through before p11 (release) Fixed: See vendor advisory.
Why it matters
Review the vendor advisory and exposure of the affected product to determine operational impact.
Detection & mitigation
- Apply vendor-provided updates or mitigations.
- Review affected product exposure and access logs.
Public PoC references
No public PoC reference has passed the current publication threshold.