CVE-2018-20131
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 · uneditedThe Code42 app before 6.8.4, as used in Code42 for Enterprise, on Linux installs with overly permissive permissions on the /usr/local/crashplan/log directory. This allows a user to manipulate symbolic links to escalate privileges, or show the contents of sensitive files that a regular user would not have access to.
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 confidenceThe Code42 (formerly CrashPlan) application for Linux installs with world-writable permissions (likely 777) on the /usr/local/crashplan/log directory. This allows any local unprivileged user to create or modify symbolic links within that directory to read sensitive files they shouldn't have access to, or potentially escalate privileges by targeting privileged processes that write to that directory.
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< 6.8.4CVSS 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
- High
- Availability
- High
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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.
-
Verify Code42/CrashPlan is installedCheck if the directory /usr/local/crashplan exists on the system using 'ls -d /usr/local/crashplan'Affected if The directory does not exist - Code42 is not installed and not affected
-
Determine the installed Code42 versionCheck the version file in /usr/local/crashplan or use the system package manager (dpkg -l crashplan or rpm -qi crashplan) to get the installed version numberAffected if Version is less than 6.8.4 - the version is within the affected range
-
Check permissions on the log directoryRun 'ls -la /usr/local/crashplan/' and examine the permissions on the 'log' subdirectory - look at the permission bits in the first column (drwxrwxrwx indicates world-writable)Affected if The log directory shows world-writable permissions such as drwxrwxrwx (mode 777) or similar allowing write access to all users
-
Inspect for suspicious symlinks in the log directoryRun 'ls -la /usr/local/crashplan/log' to list all entries - use 'file <symlink>' on any symlinks to see where they pointAffected if Symlinks exist that point to sensitive system files or privileged locations outside the normal log directory
The system is affected if Code42 version is below 6.8.4 AND the /usr/local/crashplan/log directory has world-writable permissions (mode 777 or similar allowing write access to any user).
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 data6.8.4
Upgrade Code42 app to version 6.8.4 or later which contains the permission fix. Alternatively, immediately restrict permissions on /usr/local/crashplan/log to 755 or more restrictive ownership until the upgrade can be applied.
- Consultation2.0 h
- Implementation2.0 h
- Testing1.0 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 $1,744.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2018-20131 — 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-2018-20131 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