OpenVPN from 2.6.0 through 2.6.10 in a server role accepts multiple exit notifications from authenticated clients which will extend the validity of a closing session
https://www.cisa.gov/news-events/ics-advisories/icsa-24-319-06
https://tuxcare.com/blog/ubuntu-fixes-two-openvpn-vulnerabilities/
https://www.mail-archive.com/[email protected]/msg07634.html