CVE-2022-39252: Matrix Matrix-Rust-SDK

High severity, CVSS 7.5. EPSS: 0.6% chance of exploitation in the next 30 days.

matrix-rust-sdk is an implementation of a Matrix client-server library in Rust, and matrix-sdk-crypto is the Matrix encryption library. Prior to version 0.6, when a user requests a room key from their devices, the software correctly remembers the request. When the user receives a forwarded room key, the software accepts 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 0.6 fixes this issue.

Affected products

• Matrix Matrix-Rust-SDK: before 0.6 (fixed in 0.6)

Published 2022-09-29. Last modified 2026-06-17.