CVSS 3.1
5.9 mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:NCVE-2021-40824
Medium (5.9) in matrix. EPSS 0.7% chance of exploitation in the next 30 days. Fixed in org.matrix.android:matrix-android-sdk2 1.2.2.
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.
Severity
- EPSS
- 0.7% chance of exploitation in the next 30 days; higher than 51% of CVEs (scores of 2026-10-31)
- CWE
- CWE-290
- Published
- Modified
- Record from
- the NVD, synced
Affected
- matrix:element
- matrix:matrix-android-sdk2
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-jjmc-4p83-pp26 | Maven | org.matrix.android:matrix-android-sdk2 | <1.2.2 | 1.2.2 |