Mattermost DesktopApplication · Mattermost

CVE-2024-39772

MEDIUM · 5.3 CVSS v3.1 Published 2024-09-16
Fix available
A fix is available. Upgrade to 5.9.0 or later.
See remediation →
62/100
Remediation priority · Elevated
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
Mattermost Desktop App versions <=5.8.0 fail to safeguard screen capture functionality which allows an attacker to silently capture high-quality screenshots via JavaScript APIs.

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 confidence

The Mattermost Desktop App versions 5.8.0 and earlier contain a vulnerability where JavaScript APIs used for screen capture functionality are not properly safeguarded, allowing an attacker with the ability to execute JavaScript (e.g., through a malicious message or compromised plugin) to silently capture high-quality screenshots of the user's desktop.

MitigationUpgrade Mattermost Desktop App to a version newer than 5.8.0 which includes proper safeguards for screen capture functionality.

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 DesktopApplication
Affected:< 5.9.0

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
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 checks

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

  1. Identify if Mattermost Desktop is installed
    Check for the Mattermost Desktop application on the system. On Windows, look in Program Files or the Start Menu. On macOS, check /Applications. On Linux, check common application directories or use a package manager query.
    Affected if Mattermost Desktop is installed on the system
  2. Determine the installed Mattermost Desktop version
    Open Mattermost Desktop, then navigate to Help > About Mattermost Desktop (or similar menu option depending on OS). Alternatively, check the application metadata: on Windows, right-click the executable and view Properties > Details; on macOS, right-click the app in Applications and select Get Info.
    Affected if The displayed version is 5.8.0 or earlier, or the version cannot be determined (older version may be reported differently)
  3. Compare installed version against affected range
    Compare the identified version number to the affected range: any version below 5.9.0 is vulnerable. Note that version 5.9.0 and later include the fix.
    Affected if The installed version is less than 5.9.0
  4. Verify if remote content or plugins are accessible (attack vector check)
    Consider whether the Mattermost Desktop client connects to servers that could deliver malicious JavaScript (e.g., untrusted chat servers, third-party plugins, or custom integrations). Check the server URLs configured in the client.
    Affected if The client connects to untrusted or unmanaged servers, increasing the likelihood of the JavaScript-based attack vector being exploitable

A user is affected if Mattermost Desktop version 5.8.0 or earlier is installed and the client can execute untrusted JavaScript from messages or plugins.

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.

dbcve · scoped
Upgrade available Upgrade to 5.9.0 or later
Fixed in 5.9.0
Interim mitigation

Upgrade Mattermost Desktop App to a version newer than 5.8.0 which includes proper safeguards for screen capture functionality.

Recommended fix High confidence

5.9.0

  1. Upgrade Mattermost Desktop App to version 5.9.0 or later to resolve the improper access control vulnerability in screen capture functionality

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Mattermost Desktop Scoped from the published advisory
  • Consultation3.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA3.0 h
24.0 hours of engineering $4,200
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,720.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2024-39772 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2024-39772 in production — separate from our analysis above.

No notes yet

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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