OpenZFS: user-namespace capability check allows unprivileged local authorization bypass (CVE-2026-79619) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-79619

OpenZFS: user-namespace capability check allows unprivileged local authorization bypass

Answer in brief

CVE-2026-79619 records a Unknown severity vulnerability in OpenZFS: user-namespace capability check allows unprivileged local authorization bypass. The current sources do not mark it as known exploited. The current feed maps OpenZFS/OpenZFS (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 26, 2026Updated Aug 26, 2026Source checked Aug 26, 2026First seen by HOL Aug 26, 2026Material review Aug 26, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps OpenZFS/OpenZFS (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
OpenZFS/OpenZFSgeneric	>=0 <2.2.11 \|\| >=2.3.0 <2.3.9 \|\| >=2.4.0 <2.4.4	2.2.11, 2.3.9, 2.4.4

Recommended response

Check inventory. Check lockfiles and deployed manifests for OpenZFS/OpenZFS.
Review the reported fix. Update OpenZFS/OpenZFS to 2.2.11 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 26, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 26, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 26, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.