CVE-2023-29529Network attack vector

Group-call eavesdropping via undeclared direct calls

Published Apr 14, 2023 · Updated Feb 6, 2025

Missing authorization in matrix-js-sdk before 24.1.0 allows remote authenticated users to eavesdrop on MSC3401 group calls. The group-call implementation accepts incoming direct calls before callers declare participation and exposes outbound audio and video to them. The attacker must already be present in the call room; affected participants receive no indication of the hidden listener, and legacy one-to-one calls remain unaffected.

CVSS severity5.0
Medium
EPSS probability0.54%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in matrix-js-sdk before 24.1.0 allows remote authenticated users to eavesdrop on MSC3401 group calls. The group-call implementation accepts incoming direct calls before callers declare participation and exposes outbound audio and video to them. The attacker must already be present in the call room; affected participants receive no indication of the hidden listener, and legacy one-to-one calls remain unaffected.

The record

CVE
CVE-2023-29529
Published
Apr 14, 2023
Updated
Feb 6, 2025
Vendor
The Matrix.org Foundation
Product
matrix-js-sdk
Classifications
CWE-862, T1125, T1123
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 14, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 6, 2025Record 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=< 24.1.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

The Matrix.org Foundation · matrix-js-sdkversion=< 24.1.0

Published CVSS scores

5.0GitHubCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-862Missing Authorization
T1125Video Capture
T1123Audio Capture

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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