CVE-2021-40823

medium

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.

References

https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing

https://github.com/matrix-org/matrix-js-sdk/releases/tag/v12.4.1

Details

Source: Mitre, NVD

Published: 2021-09-13

Updated: 2024-11-21

Risk Information

CVSS v2

Base Score: 4.3

Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 5.9

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Severity: Medium