CVE-2022-39254
When matrix-nio receives forwarded room keys, the receiver doesn't check if it requested the key from the forwarder
8.6
HIGH
CVSS 3.1
EPSS 0.24%
Description
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.
How to fix CVE-2022-39254
To remediate CVE-2022-39254, upgrade the affected package to a fixed version below.
- —upgrade to 0.20.0-1 or later
- —upgrade to 0.20 or later
Is CVE-2022-39254 being exploited?
Low — EPSS is 0.2%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 0.20.0-1
- from 0, < 0.20
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH8.6 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N |