Nextcloud ServerApplication · Nextcloud
CVE-2018-16464
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 · uneditedA missing access check in Nextcloud Server prior to 14.0.0 could lead to continued access to password protected link shares when the owner had changed the password.
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 confidenceNextcloud Server prior to 14.0.0 lacks a proper access validation check when users attempt to access password-protected link shares after the owner has changed the share password. This allows users who previously knew the old password to continue accessing the share without re-authentication, bypassing the new password requirement.
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
Nextcloud ServerApplication
< 14.0.0CVSS 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
- Network
- Complexity
- Low
- Privileges
- Low
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.0/AV:N/AC:L/PR:L/UI:R/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.
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Check your Nextcloud Server versionNavigate to the admin settings page or check the version file in your Nextcloud installation directory. The version is typically visible in the bottom-left corner of the admin dashboard under 'Nextcloud' or in a version.php file.Affected if The installed version is any release prior to 14.0.0 (for example, 13.0.x, 12.0.x, or earlier)
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Identify password-protected link sharesUse the Nextcloud web interface or occ command to list all existing link shares. Look for shares where a password is or was set. You can use: occ sharing:list --format=json to enumerate shares, then filter for those with password protection enabled.Affected if Any password-protected link shares exist in the system prior to version 14.0.0
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Review share authentication tokensCheck the database for oauth tokens or session tokens associated with link share access. Look in the oc_oauth2_access_tokens or oc_share table for entries that may represent authenticated share sessions that persisted across password changes.Affected if There are authentication tokens in the database that were created before a share password was modified and remain active
You are affected if you run any Nextcloud Server version below 14.0.0 and have password-protected link shares where the password may have been changed after users authenticated with the old password.
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 data14.0.0
Upgrade to Nextcloud Server 14.0.0 or later to receive the access control fix. Alternatively, revoke and recreate affected link shares to ensure all access is properly controlled.
Fix this in Nextcloud Server
Scoped from the published advisory
- Consultation2.0 h
- Implementation2.0 h
- Testing3.0 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 $2,224.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2018-16464 — 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-2018-16464 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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