dbcve.org
Mattermost MobileApplication · Mattermost

CVE-2020-14451

HIGH · 7.5 CVSS v3.1 Published 2020-06-19
Fix available
A fix is available. Upgrade to 1.29.0 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

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 · unedited
An issue was discovered in Mattermost Mobile Apps before 1.29.0. The iOS app allowed Single Sign-On cookies and Local Storage to remain after a logout, aka MMSA-2020-0013.

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 confidence

The Mattermost iOS mobile app before version 1.29.0 failed to properly clear Single Sign-On cookies and Local Storage data during the logout process. This residual authentication data persisted on the device after logout, potentially allowing subsequent users or attackers with physical access to access the previous user's session information.

MitigationUpgrade Mattermost Mobile App for iOS to version 1.29.0 or later, which implements proper cleanup of SSO cookies and Local Storage upon logout.

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
Mattermost MobileApplication
Affected:< 1.29.0

CVSS 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 checks

Work through these to decide whether this CVE applies to you.

  1. Identify installed Mattermost Mobile version on iOS
    Open the Mattermost app, go to Settings > About to view the version number, or check in the iOS App Store app listing
    Affected if The displayed version is less than 1.29.0 (for example, 1.28.x, 1.27.x, etc.)
  2. Verify logout behavior for residual session data
    Log out of the Mattermost app, then check if SSO cookies or Local Storage data still exist by inspecting the app's sandboxed data storage
    Affected if After logout, authentication cookies or session data in Local Storage remain present and are not cleared
  3. Confirm iOS platform and app type
    Verify the affected app is Mattermost Mobile for iOS (not Android or other platforms)
    Affected if The app is the iOS version of Mattermost Mobile and the version is below 1.29.0

You are affected if you have Mattermost Mobile for iOS installed with a version number lower than 1.29.0, and logout does not properly clear SSO cookies and Local Storage data.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 data
Upgrade available Upgrade to 1.29.0 or later
Fixed in 1.29.0
Interim mitigation

Upgrade Mattermost Mobile App for iOS to version 1.29.0 or later, which implements proper cleanup of SSO cookies and Local Storage upon logout.

Fix this in Mattermost Mobile Scoped from the published advisory
  • Consultation2.0 h
  • Implementation6.0 h
  • Testing3.0 h
  • Review / QA2.0 h
13.0 hours of engineering $2,290
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,664.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2020-14451 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2020-14451 in production — separate from our analysis above.

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.

What this is

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.

What belongs here
  • 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