Buffer overflow in FreeBSD
CVE-2023-3494
The fwctl driver implements a state machine which is executed when a bhyve guest accesses certain x86 I/O ports. The interface lets the guest copy a string into a buffer resident in the bhyve process' memory. A bug in the state machine implementation can result in a buffer overflowing when copying this string. Malicious, privileged software running in a guest VM can exploit the buffer overflow to achieve code execution on the host in the bhyve userspace process, which typically runs as root, mitigated by the capabilities assigned through the Capsicum sandbox available to the bhyve process.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.002 (12.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 12th percentile — 12.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
- FreeBSD — versions 13.1, 13.2, 13.1-RELEASE
Weakness classification (CWE)
References
- security.FreeBSD.org/advisories/FreeBSD-SA-23:07.bhyve.asc (vendor-advisory, Vendor Advisory)
- security.netapp.com/advisory/ntap-20230831-0006/
Frequently asked questions
- What is CVE-2023-3494?
- CVE-2023-3494 is a high-severity vulnerability in FreeBSD, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 8.8/10. Published 2023-08-01.
- How severe is CVE-2023-3494?
- High severity. CVSS v3 base score is 8.8 out of 10.