gssproxy (aka gss-proxy) before 0.8.3 does not unlock cond_mutex before pthread exit in gp_worker_main() in gp_workers.c. NOTE: An upstream comment states "We are already on a shutdown path when running the code in question, so a DoS there doesn't make any sense, and there has been no additional information provided us (as upstream) to indicate why this would be a problem.
https://pagure.io/gssproxy/c/cb761412e299ef907f22cd7c4146d50c8a792003?branch=master
https://lists.debian.org/debian-lts-announce/2021/01/msg00004.html
https://github.com/gssapi/gssproxy/compare/v0.8.2...v0.8.3
https://github.com/gssapi/gssproxy/commit/cb761412e299ef907f22cd7c4146d50c8a792003