TrueConf Server is a videoconferencing server product that has been targeted by threat actors exploiting vulnerabilities to replace client installers with malware. Affected versions include 5.3.x up to 5.3.9, 5.4.x up to 5.4.9, and 5.5.x up to 5.5.5. Patches are available in versions 5.3.9, 5.4.9, and 5.5.5.