Rapid7

vulnerability

Debian: CVE-2021-40823: node-matrix-js-sdk -- security update

Severity
4
CVSS
(AV:N/AC:M/Au:N/C:P/I:N/A:N)
Published
Sep 13, 2021
Added
May 15, 2025
Modified
Mar 30, 2026

Description

A logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK) before 12.4.1 allows a malicious Matrix homeserver present in an encrypted room to steal room encryption keys (via crafted Matrix protocol messages) that were originally sent by affected Matrix clients participating in that room. This allows the homeserver to decrypt end-to-end encrypted messages sent by affected clients.

Solution

no-fix-debian-deb-package
Title
Rapid7 Labs

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