CVE-2023-29529 | matrix-js-sdk vulnerable to invisible eavesdropping in group calls

matrix-js-sdk is the Matrix Client-Server SDK for JavaScript and TypeScript. An attacker present in a room where an MSC3401 group call is taking place can eavesdrop on the video and audio of participants using matrix-js-sdk, without their knowledge. To affected matrix-js-sdk users, the attacker will not appear to be participating in the call. This attack is possible because matrix-js-sdk's group call implementation accepts incoming direct calls from other users, even if they have not yet declared intent to participate in the group call, as a means of resolving a race condition in call setup. Affected versions do not restrict access to the user's outbound media in this case. Legacy 1:1 calls are unaffected. This is fixed in matrix-js-sdk 24.1.0. As a workaround, users may hold group calls in private rooms where only the exact users who are expected to participate in the call are present.

Published: 2023-04-14 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-29529 is rated Low Risk (34.7/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.54%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-29529

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.18% 0.54% +0.36%
2 2026-04-26 0.33% 0.18% -0.14%
3 2026-04-16 — 0.33% —

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-29529

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.0 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.1 1.4 [email protected]
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 1.4 [email protected]

Weakness enumeration for CVE-2023-29529

GitHub Security Advisory for CVE-2023-29529

GHSA-6g67-q39g-r79q · Severity: medium · Ecosystem: npm — matrix-js-sdk vulnerable to invisible eavesdropping in group calls

OS Trackers for CVE-2023-29529

vendor priority summary link
debian end-of-life CVE-2023-29529 end-of-life priority: Debian including 1 source packages (node-matrix-js-sdk), 1 status rows across 1 suites (bullseye): open 1. https://security-tracker.debian.org/tracker/CVE-2023-29529
ubuntu medium CVE-2023-29529 medium priority: Ubuntu including 1 source packages (node-matrix-js-sdk), 13 status rows across 13 suites (bionic, focal, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): ignored 6, needs-triage 4, DNE 3. https://ubuntu.com/security/CVE-2023-29529

Affected software / configurations for CVE-2023-29529

Vendor Product Version Raw CPE
matrix javascript_sdk < 24.1.0 cpe:2.3:a:matrix:javascript_sdk:*:*:*:*:*:node.js:*:*

References for CVE-2023-29529

cvelogic Threat Intelligence