CVE-2024-42347Network attack vector

Encrypted-message URL disclosure via server-controlled previews

Published Aug 6, 2024 · Updated Aug 8, 2024

Information exposure in Matrix.org matrix-react-sdk before 3.105.1 lets remote attackers controlling a homeserver read URLs in encrypted messages. The room URL-preview setting accepts homeserver-controlled account data and enables previews in end-to-end encrypted rooms, sending message URLs back to that server. Exploitation requires control of the user's homeserver; trusted homeservers and closed federations of trusted servers are not affected, and no message modification or service interruption is reported.

CVSS severity7.7
High
EPSS probability0.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information exposure in Matrix.org matrix-react-sdk before 3.105.1 lets remote attackers controlling a homeserver read URLs in encrypted messages. The room URL-preview setting accepts homeserver-controlled account data and enables previews in end-to-end encrypted rooms, sending message URLs back to that server. Exploitation requires control of the user's homeserver; trusted homeservers and closed federations of trusted servers are not affected, and no message modification or service interruption is reported.

The record

CVE
CVE-2024-42347
Published
Aug 6, 2024
Updated
Aug 8, 2024
Vendor
Matrix.org
Product
matrix-react-sdk
Classifications
CWE-359, T1119
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Aug 6, 2024CVE publishedPublication date reported by the CVE source.
  2. Aug 8, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 3.105.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Matrix.org · matrix-react-sdkversion=< 3.105.1

Published CVSS scores

7.7GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
5.1GitHub Advisory DatabaseCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N/U:Red
4.1matrix-react-sdk maintainersCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-359Exposure of Private Personal Information to an Unauthorized Actor
T1119Automated Collection

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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