CVE-2025-34189 is a medium-severity vulnerability affecting Vasion Print Virtual Appliance Host versions prior to 1.0.735 and Application versions prior to 20.0.1330, specifically in macOS and Linux client deployments. The vulnerability arises due to improper permission assignments on the local inter-process communication (IPC) files stored in the directory /opt/PrinterInstallerClient/tmp. These IPC request and response files are set with world-readable and world-writable permissions, allowing any local user on the system to create or modify these files. Because privileged daemons process these IPC files, a malicious local user can craft specially designed request files that cause these daemons to execute unauthorized actions within other user sessions. This breaks the isolation between user sessions, enabling session hijacking and unintended actions executed with elevated privileges. The vulnerability impacts system integrity and availability by allowing attackers to interfere with or disrupt normal operations. The issue is categorized under CWE-732 (Incorrect Permission Assignment for Critical Resource) and CWE-922 (Insecure Storage of Sensitive Information), highlighting the root cause as insecure file permissions on critical IPC resources. The CVSS 4.0 base score is 6.9, reflecting a medium severity with local attack vector, low attack complexity, no user interaction, and limited scope. No known exploits are currently reported in the wild, and no patches are linked yet, indicating that organizations should proactively mitigate this risk. This vulnerability is particularly relevant in environments where multiple users share access to the same host system running the Vasion Print Virtual Appliance, as local attackers can leverage this flaw to escalate privileges or disrupt printing services.

For European organizations, this vulnerability poses a risk primarily in multi-user environments such as enterprise print servers, shared workstations, or virtualized environments where the Vasion Print Virtual Appliance Host is deployed. Exploitation can lead to unauthorized actions executed by privileged daemons, potentially allowing attackers to hijack user sessions, manipulate print jobs, or disrupt printing infrastructure. This can degrade operational availability and compromise system integrity, impacting business continuity especially in sectors heavily reliant on printing services such as legal, financial, healthcare, and government institutions. Confidentiality impact is limited since the vulnerability is local and does not directly expose data externally, but integrity and availability impacts are significant. The local attack vector means that insider threats or compromised local accounts pose the greatest risk. Given the critical role of printing infrastructure in many European enterprises, exploitation could cause workflow disruptions and require costly incident response and remediation efforts.

To mitigate this vulnerability, European organizations should immediately review and correct the file permissions on the /opt/PrinterInstallerClient/tmp directory and its contents to restrict access strictly to the necessary privileged users and processes. Specifically, remove world-readable and world-writable permissions and apply the principle of least privilege. Implement strict access control lists (ACLs) or use filesystem attributes to prevent unauthorized local users from creating or modifying IPC files. Additionally, monitor the directory for unexpected file creation or modification activities using host-based intrusion detection systems (HIDS). Organizations should also isolate the Vasion Print Virtual Appliance Host on dedicated systems or virtual machines with limited user access to reduce the attack surface. Regularly update the software to the latest versions once patches become available from Vasion. Finally, conduct local user privilege audits and restrict local user accounts to minimize the number of users who can access the affected systems.