CVE-2020-14454
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 Desktop App before 4.4.0. Attackers can open web pages in the desktop application because server redirection is mishandled, aka MMSA-2020-0008.
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 Desktop App before version 4.4.0 contains a server redirection mishandling vulnerability (MMSA-2020-0008). Attackers can exploit this to cause the desktop application to open arbitrary web pages, potentially leading to phishing attacks or malicious content execution within the trusted desktop context.
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< 4.4.0CVSS 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
- Required
- Scope
- Changed
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/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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Locate Mattermost Desktop App versionOpen the Mattermost Desktop App, then navigate to Help > About Mattermost Desktop App. The version number is displayed in the dialog that appears. Alternatively, on Windows right-click the executable and select Properties > Details to view the version. On macOS, click the app name in the menu bar and select About.Affected if the displayed version is below 4.4.0 or shows no version number in that dialog
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Verify the exact version numberCompare the installed version string (for example, 4.3.0, 4.2.2, etc.) against the version 4.4.0 threshold. Ensure you have the complete version string including any patch numbers.Affected if the version number is any release prior to 4.4.0, such as 4.3.x, 4.2.x, or earlier major versions
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Confirm application is the Desktop clientVerify you are checking the Mattermost Desktop App (the Electron-based desktop client) and not the mobile app, the web browser version, or the Mattermost server software. The Desktop App appears as a standalone installed application on your system.Affected if the affected software is the Mattermost Desktop App specifically and the version is below 4.4.0
You are affected if the Mattermost Desktop App installed on your system is any version prior to 4.4.0, as this is where the server redirection vulnerability exists.
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 data4.4.0
Update Mattermost Desktop App to version 4.4.0 or later to patch the server redirection vulnerability. Users should also be educated about not clicking untrusted links within the application.
- Consultation1.0 h
- Implementation2.0 h
- Testing1.0 h
- Review / QA1.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2020-14454 — 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-2020-14454 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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- 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
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