CVE-2022-39248

matrix-android-sdk2 is the Matrix SDK for Android. Prior to version 1.5.1, 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. matrix-android-sdk2 would then additionally sign such a key backup with its device key, spilling trust over to other devices trusting the matrix-android-sdk2 device. These attacks are possible due to a protocol confusion vulnerability that accepts to-device messages encrypted with Megolm instead of Olm. matrix-android-sdk2 version 1.5.1 has been modified to only accept Olm-encrypted to-device messages and to stop signing backups on a successful decryption. 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.
Configurations

Configuration 1 (hide)

cpe:2.3:a:matrix:software_development_kit:*:*:*:*:*:android:*:*

History

30 Sep 2022, 16:24

Type Values Removed Values Added
CPE cpe:2.3:a:matrix:software_development_kit:*:*:*:*:*:android:*:*
CVSS v2 : unknown
v3 : unknown
v2 : unknown
v3 : 7.5
First Time Matrix software Development Kit
Matrix
References (CONFIRM) https://github.com/matrix-org/matrix-android-sdk2/security/advisories/GHSA-fpgf-pjjv-2qgm - (CONFIRM) https://github.com/matrix-org/matrix-android-sdk2/security/advisories/GHSA-fpgf-pjjv-2qgm - Patch, Third Party Advisory
References (MISC) https://github.com/matrix-org/matrix-android-sdk2/commit/77df720a238d17308deab83ecaa37f7a4740a17e - (MISC) https://github.com/matrix-org/matrix-android-sdk2/commit/77df720a238d17308deab83ecaa37f7a4740a17e - Patch, Third Party Advisory
References (MISC) https://matrix.org/blog/2022/09/28/upgrade-now-to-address-encryption-vulns-in-matrix-sdks-and-clients - (MISC) https://matrix.org/blog/2022/09/28/upgrade-now-to-address-encryption-vulns-in-matrix-sdks-and-clients - Vendor Advisory
References (MISC) https://github.com/matrix-org/matrix-android-sdk2/releases/tag/v1.5.1 - (MISC) https://github.com/matrix-org/matrix-android-sdk2/releases/tag/v1.5.1 - Release Notes, Third Party Advisory

28 Sep 2022, 20:20

Type Values Removed Values Added
New CVE

Information

Published : 2022-09-28 20:15

Updated : 2023-12-10 14:35


NVD link : CVE-2022-39248

Mitre link : CVE-2022-39248

CVE.ORG link : CVE-2022-39248


JSON object : View

Products Affected

matrix

  • software_development_kit
CWE
CWE-287

Improper Authentication

CWE-322

Key Exchange without Entity Authentication