CVE-2022-39254

When matrix-nio receives forwarded room keys, the receiver doesn't check if it requested the key from the forwarder

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.

Category

8.6
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.06%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: poljar matrix-nio
Published at:
Updated at:

References

Link Tags
https://github.com/poljar/matrix-nio/security/advisories/GHSA-w4pr-4vjg-hffh third party advisory
https://github.com/poljar/matrix-nio/commit/b1cbf234a831daa160673defd596e6450e9c29f0 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2022-39254?
CVE-2022-39254 has been scored as a high severity vulnerability.
How to fix CVE-2022-39254?
To fix CVE-2022-39254, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2022-39254 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2022-39254 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2022-39254?
CVE-2022-39254 affects poljar matrix-nio.
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