CVE catalog
CVE-2021-40823
UBUNTU-CVE-2021-40823
- Severity
- Unknown
- Published
- Updated
- Source
- [NVD] · [CVE record]
- EPSS
- 0.66% · Oct 25, 2026
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 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 homeserver to decrypt end-to-end encrypted messages sent by affected clients.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | node-matrix-js-sdk | 11 | 9.11.0+~cs9.9.16-1 | vulnerable |
| Debian | node-matrix-js-sdk | 11 | 9.11.0+~cs9.9.16-2 | vulnerable |
| Debian | node-matrix-js-sdk | 11 | 9.3.0+~cs9.9.16-2 | vulnerable |
| Debian | node-matrix-js-sdk | 11 | 9.7.0~~rc1+~cs9.9.16-1 | vulnerable |
| Debian | node-matrix-js-sdk | 11 | 9.7.0~~rc1+~cs9.9.16-2 | vulnerable |
| Ubuntu | node-matrix-js-sdk | 20.04 | 0.9.2-1 | vulnerable |
| Ubuntu | node-matrix-js-sdk | 22.04 | 9.3.0+~cs9.9.16-2 | vulnerable |
| Ubuntu | node-matrix-js-sdk | 22.04 | 9.11.0+~cs9.9.16-1 | vulnerable |
| Ubuntu | node-matrix-js-sdk | 24.04 | 9.11.0+~cs9.9.16-2 | vulnerable |
Fixed-version evidence
OpenFactory catalog packages
No matching packages in this catalog.
Observed: