CVE-2016-11066
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 · uneditedAn issue was discovered in Mattermost Server before 3.2.0. The initial_load API disclosed unnecessary personal information.
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 · moderate confidenceMattermost Server before version 3.2.0 had an information disclosure vulnerability in the initial_load API endpoint, which exposed unnecessary personal information about users that should not have been included in the API response.
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< 3.2.0CVSS 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
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/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.
-
Identify the installed Mattermost Server versionAccess the Mattermost System Console and navigate to About > Mattermost or check the version displayed on the login page. Alternatively, check the server logs or package metadata where Mattermost Server is installed.Affected if The installed version is anything earlier than 3.2.0 (e.g., 3.1.x, 3.0.x, 2.x series)
-
Verify the initial_load API endpoint is accessibleMake an authenticated GET request to the /api/v1/initial_load endpoint on the Mattermost server (e.g., https://your-mattermost-url/api/v1/initial_load) using a valid user session token.Affected if The API endpoint returns a response, confirming it is exposed and reachable
-
Inspect the initial_load API response for excessive user dataExamine the JSON response from the initial_load endpoint and look for any user-related fields that contain personal information beyond what is strictly necessary for the initial load function.Affected if The response contains user data fields that are not required for the initial load functionality, indicating information is being over-disclosed
A Mattermost Server installation is affected if it is version 3.2.0 or earlier and the initial_load API endpoint is accessible, as the endpoint will return unnecessary personal information in its response.
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 data3.2.0
Upgrade Mattermost Server to version 3.2.0 or later to receive the patch that filters unnecessary personal information from the initial_load API response.
- Consultation1.0 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 $1,664.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2016-11066 — 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-2016-11066 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