8.6
HIGH
CVE-2022-39248
Matrix-Android-SDK2 Megolm/Olm Encryption Protocol Confusion Vulnerability
Description

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.

INFO

Published Date :

Sept. 28, 2022, 8:15 p.m.

Last Modified :

Sept. 30, 2022, 4:24 p.m.

Remotely Exploitable :

Yes !

Impact Score :

4.0

Exploitability Score :

3.9
Affected Products

The following products are affected by CVE-2022-39248 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Matrix software_development_kit
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2022-39248.

URL Resource
https://github.com/matrix-org/matrix-android-sdk2/commit/77df720a238d17308deab83ecaa37f7a4740a17e Patch Third Party Advisory
https://github.com/matrix-org/matrix-android-sdk2/releases/tag/v1.5.1 Release Notes Third Party Advisory
https://github.com/matrix-org/matrix-android-sdk2/security/advisories/GHSA-fpgf-pjjv-2qgm Patch Third Party Advisory
https://matrix.org/blog/2022/09/28/upgrade-now-to-address-encryption-vulns-in-matrix-sdks-and-clients Vendor Advisory

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2022-39248 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2022-39248 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Initial Analysis by [email protected]

    Sep. 30, 2022

    Action Type Old Value New Value
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
    Changed Reference Type https://github.com/matrix-org/matrix-android-sdk2/commit/77df720a238d17308deab83ecaa37f7a4740a17e No Types Assigned https://github.com/matrix-org/matrix-android-sdk2/commit/77df720a238d17308deab83ecaa37f7a4740a17e Patch, Third Party Advisory
    Changed Reference Type https://github.com/matrix-org/matrix-android-sdk2/releases/tag/v1.5.1 No Types Assigned https://github.com/matrix-org/matrix-android-sdk2/releases/tag/v1.5.1 Release Notes, Third Party Advisory
    Changed Reference Type https://github.com/matrix-org/matrix-android-sdk2/security/advisories/GHSA-fpgf-pjjv-2qgm No Types Assigned https://github.com/matrix-org/matrix-android-sdk2/security/advisories/GHSA-fpgf-pjjv-2qgm Patch, Third Party Advisory
    Changed Reference Type https://matrix.org/blog/2022/09/28/upgrade-now-to-address-encryption-vulns-in-matrix-sdks-and-clients No Types Assigned https://matrix.org/blog/2022/09/28/upgrade-now-to-address-encryption-vulns-in-matrix-sdks-and-clients Vendor Advisory
    Added CPE Configuration OR *cpe:2.3:a:matrix:software_development_kit:*:*:*:*:*:android:*:* versions up to (excluding) 1.5.1
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.09 }} -0.00%

score

0.36860

percentile

CVSS31 - Vulnerability Scoring System
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