Executive brief
Parallels Desktop's display service runs with root privileges and listens on a world-writable socket, allowing any local user to connect. An attacker can exploit command-injection flaws in the appliance installation feature to execute arbitrary commands with root privileges. This could allow a local user to gain complete control of the system and access all data.
Technical details
The vulnerability involves multiple weaknesses in prl_disp_service, a root-privileged daemon: (1) the socket /var/run/prl_disp_service.socket is world-writable, (2) local authentication (PrlSrv_LoginLocal) lacks proper validation, and (3) the PrlSrv_InstallAppliance function constructs a tar command with unsanitized user input. When an attacker specifies an appliance folder path containing quotes, Qt's QProcess::splitCommand parser treats the quote as a command-line separator, injecting additional tar flags. On macOS, the --use-compress-program flag allows execution of arbitrary programs as root. No patch has been publicly disclosed, though Parallels Desktop 27.0.2 is mentioned as addressing security vulnerabilities.
Affected products
- Parallels Desktop for Mac 26 and earlier, 27.0.0–27.0.1
Timeline
- 2026-09-14: disclosed
- 2026-09-17: patched: Parallels Desktop 27.0.2 (58673) released