CVE-2025-57848 is a vulnerability identified in Red Hat OpenShift Virtualization 4, specifically affecting container-native virtualization images. The root cause is the /etc/passwd file being created during the container image build process with group-writable permissions. This misconfiguration allows any user who can execute commands inside the container and is a member of the root group to modify the /etc/passwd file. By modifying this file, an attacker can add new user entries with arbitrary user IDs, including UID 0, which corresponds to root privileges. This effectively enables privilege escalation within the container environment, granting the attacker full root access inside the container. The vulnerability requires the attacker to have command execution capabilities inside the container and membership in the root group, which is a high privilege level within the container context. The CVSS v3.1 score is 5.2 (medium severity), reflecting the need for high privileges to exploit and the limited impact on confidentiality but significant impact on integrity and some impact on availability within the container. There are no known exploits in the wild at the time of publication. The vulnerability does not directly compromise the host system but can undermine container isolation if combined with other vulnerabilities. The issue stems from insecure default permissions during image build time, highlighting the importance of secure container build practices and permission hardening.

For European organizations deploying Red Hat OpenShift Virtualization 4, this vulnerability poses a risk of privilege escalation within containerized workloads. Attackers who gain limited access inside containers and have root group membership can escalate to full root privileges inside the container, potentially allowing them to manipulate containerized applications, access sensitive data within the container, or disrupt container operations. Although the vulnerability does not directly affect the host OS, compromised containers can be leveraged as footholds for lateral movement or further attacks if combined with other vulnerabilities. This risk is particularly relevant for organizations running multi-tenant or sensitive workloads in containerized environments, such as financial institutions, healthcare providers, and critical infrastructure operators in Europe. The medium severity rating suggests that while exploitation requires elevated privileges, the impact on container integrity and availability can be significant. Failure to address this vulnerability could lead to data integrity issues, service disruptions, and increased attack surface within containerized deployments.

European organizations should immediately review and update their container build pipelines to ensure that sensitive files like /etc/passwd are created with secure, non-group-writable permissions. Applying vendor patches or updates from Red Hat as soon as they become available is critical. Until patches are applied, organizations should audit container images for permission misconfigurations and rebuild any affected images with corrected permissions. Restrict membership of the root group within containers to only trusted processes and users to reduce the risk of exploitation. Implement runtime security controls that monitor and restrict unauthorized modifications to critical system files within containers. Employ container security best practices such as using minimal base images, enabling user namespaces, and applying strict access controls. Regularly scan container images for vulnerabilities and misconfigurations using specialized tools. Additionally, monitor container logs and behaviors for signs of privilege escalation attempts. Finally, consider network segmentation and isolation strategies to limit the impact of compromised containers.