Parallels Desktop flaw allows local users to gain root access

Researchers at JFrog have identified a security vulnerability in Parallels Desktop for Mac, designated as CVE-2026-90894 and nicknamed ‘ParaShells’. The flaw allows any local account on a Mac to escalate privileges to full root control of the host machine.

The vulnerability is particularly risky for developer machines and shared workstations, such as those in university labs or offices. An attacker could use common entry points, like a compromised Homebrew formula or a malicious npm preinstall script, to gain standard user access and then exploit the flaw to seize complete system control. Once root access is achieved, attackers can access other users’ files, swap system software, and maintain persistence.

The exploit chain involves an argument-injection bug confirmed in Parallels Desktop version 26.4.0 running on Apple silicon. The vulnerability relies on a combination of factors: a world-writable Unix socket, a client-authentication scheme that verifies peer credentials instead of a Team ID, and an argument-injection flaw during the unpacking of appliance files.