CVSS 3.1
6.5 mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:NCVE-2022-39254
Medium (6.5) in matrix-nio project matrix-nio. EPSS 0.7% chance of exploitation in the next 30 days. Fixed in matrix-nio 0.20.
matrix-nio is a Python Matrix client library, designed according to sans I/O principles. Prior to version 0.20, when a users requests a room key from their devices, the software correctly remember the request. Once they receive a forwarded room key, they accept it without checking who the room key came from. This allows homeservers to try to insert room keys of questionable validity, potentially mounting an impersonation attack. Version 0.20 fixes the issue.
Severity
- EPSS
- 0.7% chance of exploitation in the next 30 days; higher than 52% of CVEs (scores of 2026-10-31)
- CWEs
- CWE-287, CWE-322
- Published
- Modified
- Record from
- the NVD, synced
Affected
- matrix-nio_project:matrix-nio
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-w4pr-4vjg-hffh | PyPI | matrix-nio | <0.20 | 0.20 |
| PYSEC-2026-842 | PyPI | matrix-nio | <0.20 | 0.20 |
References
- https://github.com/poljar/matrix-nio/commit/b1cbf234a831daa160673defd596e6450e9c29f0
- https://github.com/poljar/matrix-nio/security/advisories/GHSA-w4pr-4vjg-hffh
- https://github.com/poljar/matrix-nio/commit/b1cbf234a831daa160673defd596e6450e9c29f0
- https://github.com/poljar/matrix-nio/security/advisories/GHSA-w4pr-4vjg-hffh