{"id":"CVE-2021-29631","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-29631","generatedAt":"2026-10-27T22:25:33.122Z","title":"A malicious guest may cause the device model to operate on uninitialized I/O vectors leading to memory corruption, crashing of the bhyve process, and possibly arbitrary code execution in the bhyve process.","description":"In FreeBSD 13.0-STABLE before n246941-20f96f215562, 12.2-STABLE before r370400, 11.4-STABLE before r370399, 13.0-RELEASE before p4, 12.2-RELEASE before p10, and 11.4-RELEASE before p13, certain VirtIO-based device models in bhyve failed to handle errors when fetching I/O descriptors. A malicious guest may cause the device model to operate on uninitialized I/O vectors leading to memory corruption, crashing of the bhyve process, and possibly arbitrary code execution in the bhyve process.","published":"2021-08-30T18:15:09.000Z","lastModified":"2026-06-17T03:48:04.000Z","status":"Modified","sourceIdentifier":"secteam@freebsd.org","cvss":{"version":"3.1","score":7.8,"severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"},"cwe":["CWE-908"],"affected":["freebsd/freebsd"],"epss":{"score":0.00286,"percentile":0.20906,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.29%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://security.FreeBSD.org/advisories/FreeBSD-SA-21:13.bhyve.asc","tags":["Vendor Advisory"],"source":"secteam@freebsd.org"},{"url":"https://security.netapp.com/advisory/ntap-20210923-0004/","tags":["Third Party Advisory"],"source":"secteam@freebsd.org"},{"url":"https://security.FreeBSD.org/advisories/FreeBSD-SA-21:13.bhyve.asc","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.netapp.com/advisory/ntap-20210923-0004/","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-29631","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}