{"id":"CVE-2026-49429","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-49429","generatedAt":"2026-10-28T02:19:32.962Z","title":"A local user with the \"userused\" delegated ZFS permission can trigger a kernel heap overflow via the ZFS_IOC_USERSPACE_MANY ioctl, potentially escalating privileges.","description":"The ZFS_IOC_USERSPACE_MANY ioctl, used by zfs-userspace(8), truncated a 64-bit output buffer size to a 32-bit integer for the kernel allocation, but used the original 64-bit size as the buffer limit when writing records.\n\nA local user with the \"userused\" delegated ZFS permission can trigger a kernel heap overflow via the ZFS_IOC_USERSPACE_MANY ioctl, potentially escalating privileges.","published":"2026-08-19T06:17:43.000Z","lastModified":"2026-09-01T20:05:51.000Z","status":"Analyzed","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-122"],"affected":["freebsd/freebsd"],"epss":{"score":0.00153,"percentile":0.04366,"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 (0.15%). 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-26:40.zfs.asc","tags":["Vendor Advisory"],"source":"secteam@freebsd.org"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-49429","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."}