A remote unauthorized attacker with network access via port 4307/TCP to the TrueConf server versions 5.3.X to 5.3.9, 5.4.X to 5.4.9, 5.5.X to 5.5.5, and earlier could use a specially crafted script to break out of the isolated environment and execute arbitrary code on the host system.
Conduct a scan for indicators of compromise. In the event of detecting indicators of compromise, change passwords for accounts that may have been compromised and contact Kaspersky ICS CERT at ics-cert@kaspersky.com for further instructions and assistance in investigating the incident.
Update TrueConf server to versions 5.3.9, 5.4.9 or 5.5.5.