dbcve.org
Matrix React SdkFramework / library · Matrix

CVE-2024-42347

MEDIUM · 6.5 CVSS v3.1 Published 2024-08-06
Fix available
A fix is available. Upgrade to 3.105.1 or later.
See remediation →
71/100
Remediation priority · Elevated
Remotely reachable 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
matrix-react-sdk is a react-based SDK for inserting a Matrix chat/voip client into a web page. A malicious homeserver could manipulate a user's account data to cause the client to enable URL previews in end-to-end encrypted rooms, in which case any URLs in encrypted messages would be sent to the server. This was patched in matrix-react-sdk 3.105.0. Deployments that trust their homeservers, as well as closed federations of trusted servers, are not affected. Users are advised to upgrade. There are no known workarounds for this vulnerability.

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

A malicious homeserver can manipulate a user's account data to enable URL previews in end-to-end encrypted rooms. When enabled, any URLs in encrypted messages are sent to the server (requiring decryption), effectively leaking the URLs and breaking E2EE confidentiality.

MitigationUpgrade matrix-react-sdk to version 3.105.0 or later. Only use trusted homeservers or closed federations of trusted servers.

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
Matrix React SdkFramework / library
Affected:< 3.105.1

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
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/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. Check matrix-react-sdk version
    Examine your package.json file or run 'npm list matrix-react-sdk' to determine the installed version of the matrix-react-sdk package.
    Affected if The installed version is lower than 3.105.1.
  2. Verify URL previews are enabled
    Navigate to Settings > Security & Privacy in your Matrix client (such as Element) and locate the URL preview setting. Check whether URL previews are turned on.
    Affected if URL previews are enabled in the client settings.
  3. Confirm E2EE room usage
    Identify whether you participate in end-to-end encrypted rooms (rooms with a lock icon). The vulnerability specifically affects encrypted messages in these rooms.
    Affected if You use end-to-end encrypted rooms with URL previews enabled.

You are affected if you are using matrix-react-sdk version below 3.105.1 and have URL previews enabled, particularly in end-to-end encrypted rooms where URLs in messages could be leaked to your homeserver.

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 3.105.1 or later
Fixed in 3.105.1
Interim mitigation

Upgrade matrix-react-sdk to version 3.105.0 or later. Only use trusted homeservers or closed federations of trusted servers.

Recommended fix High confidence

matrix-react-sdk 3.105.1

  1. Identify the package.json file in your project that contains the matrix-react-sdk dependency
  2. Run 'npm list matrix-react-sdk' or check package.json to confirm the current installed version
  3. Run 'npm install [email protected]' to upgrade to the fixed version, or use 'npm install matrix-react-sdk@latest' to get the latest stable release
  4. After installation, rebuild your application to incorporate the updated SDK
  5. Verify the upgrade was successful by checking the installed version with 'npm list matrix-react-sdk'
  6. Test that URL previews are not automatically enabled in encrypted rooms as expected after the fix

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

Fix this in Matrix React Sdk Scoped from the published advisory
  • Consultation2.0 h
  • Implementation3.0 h
  • Testing2.0 h
  • Review / QA1.0 h
8.0 hours of engineering $1,420
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,272.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2024-42347 — 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-2024-42347 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