CVE-2018-16588
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 · uneditedPrivilege escalation can occur in the SUSE useradd.c code in useradd, as distributed in the SUSE shadow package through 4.2.1-27.9.1 for SUSE Linux Enterprise 12 (SLE-12) and through 4.5-5.39 for SUSE Linux Enterprise 15 (SLE-15). Non-existing intermediate directories are created with mode 0777 during user creation. Given that they are world-writable, local attackers might use this for privilege escalation and other unspecified attacks. NOTE: this would affect non-SUSE users who took useradd.c code from a 2014-04-02 upstream pull request; however, no non-SUSE distribution is known to be affected.
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 confidenceIn SUSE's useradd command from the shadow package, when creating a new user, any non-existing intermediate directories in the user's home directory path are created with mode 0777 (world-writable). This occurs in both SLE-12 (through version 4.2.1-27.9.1) and SLE-15 (through version 4.5-5.39). Local attackers can exploit these world-writable directories to gain elevated privileges.
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<= 4.2.1-27.9.1<= 4.5-5.39CVSS 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.
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Identify the installed shadow package version on SUSE/SLESRun: rpm -q shadow or zypper se shadow and note the version numberAffected if The version is 4.2.1-27.9.1 or earlier for SLE-12, or 4.5-5.39 or earlier for SLE-15
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Verify the system is a SUSE-based Linux distributionRun: cat /etc/os-release or lsb_release -a and confirm the vendor is SUSE or openSUSEAffected if The system is running SLE-12 or SLE-15 (or openSUSE Leap based on these versions)
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Create a test user with a home directory path containing a non-existing intermediate directoryRun a command like: useradd -m -d /nonexistent/testdir/testuser testuser && ls -ld /nonexistent /nonexistent/testdirAffected if The intermediate directories are created with permissions 0777 (drwxrwxrwx)
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Inspect existing user home directory paths for world-writable intermediate directoriesRun: for dir in /home/*; do ls -ld "$dir"; done and check parent directories of user home paths for permissions 0777Affected if Any parent directory in a user's home path has mode 0777 instead of 0755 or more restrictive
A system is affected if it runs a SUSE/SLES version with shadow package <= 4.2.1-27.9.1 (SLE-12) or <= 4.5-5.39 (SLE-15) AND has intermediate directories in user home paths created with mode 0777.
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 dataApply SUSE security updates to the shadow package to fix the overly permissive directory creation permissions. The intermediate directories should be created with restrictive permissions (e.g., 0755) rather than 0777.
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,088.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2018-16588 — 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-2018-16588 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
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- Version or environment caveats, and links to real fixes
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