Description
On Linux, several OpenZFS ioctl authorization checks accept a capability held only within a user-created, unprivileged namespace as equivalent to real host privilege, allowing an unprivileged local user to perform operations that should require root. Affected operations include pool-administrative operations (eg create, import, destroy), pool event log access (zpool events) and fault injection (zinject). Exploiting the problem requires only that the local user is permitted to open /dev/zfs (governed by local device permissions) and that the kernel permits unprivileged user namespace creation. No prior access to the target pool or its underlying devices is needed.
References6
Metrics
- CVSS 4.0
-
7.3
HIGH
Score source: CNA
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 10 · as of 9 November 2026
- CWE
- CWE-863
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