Auth bypass in FreeBSD

CVE-2026-49431

The ZFS_IOC_SET_PROP ioctl, used by zfs-set(8), incorrectly validated the calling user such that an unprivileged user is able to set metadata on a dataset indicating that the dataset has received properties from a zfs-recv(8) stream. Any local user can set the internal ZFS metadata flag "$hasrecvd" on datasets via ZFS_IOC_SET_PROP.

Vulnerability class: Broken Access Control

Published · last modified .

CVSS v3 metric

CVSS v3 base score 3.3 (Low). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N.

EPSS exploit prediction

EPSS: 0.001 (1.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 2nd percentile — 1.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-49431: held from 0.001 to 0.001.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: +0.000

Affected products

  • FreeBSD — versions 14.3, 15.0, 14.4

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-49431?
CVE-2026-49431 is a low-severity vulnerability in FreeBSD, classified under Incorrect Authorization. CVSS score: 3.3/10. Published 2026-08-19.
How severe is CVE-2026-49431?
Low severity. CVSS v3 base score is 3.3 out of 10.