Ubuntu LinuxOperating system · Canonical
CVE-2016-1581
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedLXD before 2.0.2 uses world-readable permissions for /var/lib/lxd/zfs.img when setting up a loop based ZFS pool, which allows local users to copy and read data from arbitrary containers via unspecified vectors.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceLXD before version 2.0.2 creates the ZFS pool image file (/var/lib/lxd/zfs.img) with world-readable permissions (0644) when setting up a loop-based ZFS storage pool. This allows any local unprivileged user on the system to read the raw disk image file and potentially extract sensitive data from containers.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
Ubuntu LinuxOperating system
= 15.10= 16.04
LxdApplication
<= 2.0.1CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
-
Check LXD versionRun 'lxd --version' or 'snap list lxd' or check package version with 'dpkg -l lxd'Affected if Version is 2.0.1 or earlier on Ubuntu 15.10 or 16.04
-
Identify storage pool typeRun 'lxc storage list' or 'lxc info' to see configured storage pools. If ZFS is listed, check pool configuration with 'lxc storage show <pool-name>'Affected if A ZFS storage pool is configured using the loop-based backend (zfs.img file)
-
Verify ZFS image file existsCheck if /var/lib/lxd/zfs.img exists using 'ls -la /var/lib/lxd/zfs.img'Affected if The file /var/lib/lxd/zfs.img exists on the system
-
Inspect file permissionsRun 'ls -la /var/lib/lxd/zfs.img' and examine the permission bits in the first columnAffected if Permissions show 'rw-r--r--' (0644) or any world-readable setting, meaning any local user can read the file
Affected if running LXD <= 2.0.1 on Ubuntu 15.10/16.04 with a loop-based ZFS storage pool where /var/lib/lxd/zfs.img has world-readable permissions (0644 or more open).
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataUpgrade LXD to version 2.0.2 or later, which sets restrictive permissions (0600) on the zfs.img file. Alternatively, manually fix permissions on existing installations with 'chmod 600 /var/lib/lxd/zfs.img' and ensure proper ownership.
Fix this in Ubuntu Linux
Scoped from the published advisory
- Consultation2.0 h
- Implementation2.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,984.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2016-1581 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2016-1581 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data