CVE-2021-40824

A logic error in the room key sharing functionality of Element Android before 1.2.2 and matrix-android-sdk2 (aka Matrix SDK for Android) before 1.2.2 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 attacker to decrypt end-to-end encrypted messages sent by affected clients.

CVSS v3 5.9 MEDIUM
CVSS v2.0 4.3 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

4.3^/10

CVSS v2.0 : MEDIUM

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

Exploitability : 8.6 / Impact : 2.9

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact NONE

References

Link	Resource
https://github.com/matrix-org/matrix-android-sdk2/releases/tag/v1.2.2	Patch Third Party Advisory
https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:matrix:element::::::android::*
	cpe:2.3:a:matrix:matrix-android-sdk2::::::android::*

History

No history.

Information

Published : 2021-09-13 19:15

Updated : 2023-08-08 14:22

NVD link : CVE-2021-40824

Mitre link : CVE-2021-40824

CVE.ORG link : CVE-2021-40824

JSON object : View

Products Affected

matrix

element
matrix-android-sdk2

CWE

CWE-290

Authentication Bypass by Spoofing

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