In FreeRDP less than or equal to 2.0.0, an outside controlled array index is used unchecked for data used as configuration for sound backend (alsa, oss, pulse, ...). The most likely outcome is a crash of the client instance followed by no or distorted sound or a session disconnect. If a user cannot upgrade to the patched version, a workaround is to disable sound for the session. This has been patched in 2.1.0.
https://lists.debian.org/debian-lts-announce/2023/10/msg00008.html
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-w67c-26c4-2h9w
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00080.html