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CVE-2021-40824

5.9 MEDIUM

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) ...

Published: 2021-09-13 · Last updated: 2026-06-17

Severity and scoring

CVSS
5.9 MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
CWE
CWE-290

Affected products

VendorProduct
matrixelement, matrix-android-sdk2

Description

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.

Source: NVD

References

Related CVEs

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  • CVE-2021-40823 — 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 ... (5.9 MEDIUM)
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