CVSS 3.1
7.8 highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HCVE-2026-49429
High (7.8) in freebsd freebsd. EPSS 0.2% chance of exploitation in the next 30 days.
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.
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.
Severity
- EPSS
- 0.2% chance of exploitation in the next 30 days; higher than 4% of CVEs (scores of 2026-10-31)
- CWE
- CWE-122
- Published
- Modified
- Record from
- the NVD, synced
Affected
- freebsd:freebsd