CVE-2017-18902
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 4.1.0, 4.0.4, and 3.10.3. It allows attackers to discover team invite IDs via team API endpoints.
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 confidenceMattermost Server before versions 4.1.0, 4.0.4, and 3.10.3 contains an information disclosure vulnerability where team invite IDs can be discovered through team API endpoints without authentication, potentially allowing unauthorized team access.
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< 3.10.3>= 4.0.0, < 4.0.4CVSS 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
- Network
- Complexity
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/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 query the API endpoint /api/v4/system/ping without authentication to retrieve the version information from the server response.Affected if The displayed version is earlier than 3.10.3, OR falls within the range 4.0.0 to 4.0.3 inclusive.
-
Verify if unauthenticated team API endpoints are accessibleSend a GET request to the team API endpoint (such as /api/v4/teams/{team_id}/invite/ids or similar team-related endpoints) without providing any authentication credentials or session token.Affected if The server returns a successful HTTP response with team invite IDs or sensitive team information without requiring authentication.
-
Check for exposure of team invite IDs in API responsesExamine the JSON response from unauthenticated team API calls and look for fields containing invite IDs, invite links, or team join tokens that should not be publicly accessible.Affected if The API response contains team invite IDs, invite links, or team-specific identifiers that should be protected.
-
Review server configuration for authentication enforcementInspect the Mattermost config.json file or the authentication settings in the System Console to verify whether API endpoint access controls are properly enforcing authentication.Affected if The configuration shows that team API endpoints are accessible without authentication or authentication is disabled for team-related endpoints.
A user is affected if their Mattermost Server version is below 3.10.3 or between 4.0.0 and 4.0.3 inclusive, AND unauthenticated access to team API endpoints reveals invite IDs or sensitive team information.
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 data3.10.34.0.4
Upgrade Mattermost Server to version 4.1.0, 4.0.4, 3.10.3 or later. Additionally, review API access logs for suspicious enumeration of team invite IDs and consider implementing additional access controls on sensitive API endpoints.
- 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-2017-18902 — 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-2017-18902 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