CVE-2021-40823

Published: Sep 13, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSACWE-290

5.9MEDIUM

NVD MITRE

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:HAttack Complexity

High

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:HConfidentiality

High

I:NIntegrity

None

A:NAvailability

None

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Weaknesses

CWE-290

Affected Products

matrix

oss-project·GBaka javascript sdk, matrix irc bridge, synapse

javascript sdkLibraryLibrary

Communications / messaging-chat

npm

package-ecosystem

matrix-js-sdk

OSS Libraries

and 1 more affected products View all →

Exploitability

Official Patch Available

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Initial Access

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References

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

github.com

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

matrix.org

https://github.com/matrix-org/matrix-js-sdk/security/advisories/GHSA-23cm-x6j7-6hq3

github.com

and 3 more references View all →

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