An attacker with local access the to medical office computer can
escalate his Windows user privileges to "NT AUTHORITY\SYSTEM" by
exploiting a command injection vulnerability in the Elefant Update
Service. The command injection can be exploited by communicating with
the Elefant Update Service which is running as "SYSTEM" via Windows
Named Pipes.The Elefant Software Updater (ESU) consists of two components. An ESU
service which runs as "NT AUTHORITY\SYSTEM" and an ESU tray client
which communicates with the service to update or repair the installation
and is running with user permissions. The communication is implemented
using named pipes. A crafted message of type
"MessageType.SupportServiceInfos" can be sent to the local ESU service
to inject commands, which are then executed as "NT AUTHORITY\SYSTEM".
Description: CAPEC-234 Hijacking a privileged process
Solutions
The vendor fixed the issue in version 1.4.2.1811 (or higher) of the Elefant Software Updater which can be downloaded from hasomed.de/produkte/elefant/ https://hasomed.de/produkte/elefant/ or via the Elefant Software Updater itself.
Configurations
Workarounds
While workarounds such as modifying the Elefant windows firewall
rules and manually adjusting file permissions in the installation folder
are feasible workarounds for some of the vulnerabilities, it is
recommended to install the patches provided by the vendor.
Exploits
Credits
finder
Tobias Niemann, SEC Consult Vulnerability Lab
finder
Daniel Hirschberger, SEC Consult Vulnerability Lab