CVE-2022-39251

HIGH8.6EPSS 0.28%

matrix-js-sdk subject to user spoofing via Olm/Megolm protocol confusion

發布日:2022/9/30修改日:2026/4/28

描述

Matrix Javascript SDK is the Matrix Client-Server SDK for JavaScript. Prior to version 19.7.0, an attacker cooperating with a malicious homeserver can construct messages that legitimately appear to have come from another person, without any indication such as a grey shield. Additionally, a sophisticated attacker cooperating with a malicious homeserver could employ this vulnerability to perform a targeted attack in order to send fake to-device messages appearing to originate from another user. This can allow, for example, to inject the key backup secret during a self-verification, to make a targeted device start using a malicious key backup spoofed by the homeserver. These attacks are possible due to a protocol confusion vulnerability that accepts to-device messages encrypted with Megolm instead of Olm. Starting with version 19.7.0, matrix-js-sdk has been modified to only accept Olm-encrypted to-device messages. Out of caution, several other checks have been audited or added. This attack requires coordination between a malicious home server and an attacker, so those who trust their home servers do not need a workaround.

受影響套件(2)

CVSS 分數

來源版本嚴重程度向量
osvCVSS 3.1HIGH8.6CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N

參考連結(8)