CVE-2025-4953 is a vulnerability discovered in Podman, a popular container management tool used within Red Hat OpenShift Container Platform 4.12. The flaw arises during the container image build process when the RUN command uses a bind mount (RUN --mount=type=bind). Normally, data written to these bind mounts during the build should be ephemeral and discarded after the build completes. However, due to this vulnerability, files created inside the container during the build persist in the temporary build context directory on the host system. This behavior can inadvertently expose sensitive files or data generated during the build process to unauthorized users who have access to the host filesystem. The vulnerability impacts confidentiality and integrity since sensitive build artifacts or secrets could be leaked or tampered with. The CVSS 3.1 score of 7.4 reflects a high severity, with network attack vector (AV:N), high attack complexity (AC:H), no privileges required (PR:N), and no user interaction (UI:N). The scope remains unchanged (S:U), but the impact on confidentiality and integrity is high (C:H/I:H), while availability is unaffected (A:N). No known exploits have been reported yet, but the nature of the vulnerability makes it a significant risk for containerized environments, especially in multi-tenant or shared infrastructure scenarios. The issue is specific to Red Hat OpenShift Container Platform 4.12 and Podman versions used therein, emphasizing the need for targeted remediation.

For European organizations, this vulnerability poses a risk of unauthorized disclosure of sensitive build-time data, including secrets, credentials, or proprietary code, due to insecure temporary file handling during container builds. This can lead to intellectual property theft, compliance violations (e.g., GDPR if personal data is exposed), and potential lateral movement within infrastructure if attackers gain access to exposed files. Organizations relying heavily on containerization and Red Hat OpenShift for cloud-native deployments, CI/CD pipelines, or multi-tenant environments are particularly vulnerable. The persistence of files on the host undermines container isolation principles, increasing the attack surface. Additionally, the high confidentiality and integrity impact could disrupt secure software supply chains and damage organizational reputation. Although no active exploits are known, the vulnerability's characteristics make it attractive for attackers targeting build environments to harvest sensitive information or implant malicious artifacts.

1. Apply official patches or updates from Red Hat as soon as they become available to address the underlying Podman issue. 2. Restrict filesystem permissions on temporary build context directories to limit access only to trusted build processes and administrators. 3. Implement strict access controls and monitoring on build hosts to detect unauthorized access to temporary directories. 4. Use ephemeral or isolated build environments that are destroyed immediately after builds complete to prevent leftover files. 5. Avoid including sensitive data directly in container builds or bind mounts; use secure secret management solutions instead. 6. Audit and review container build scripts and processes to ensure no sensitive data is written to bind mounts during builds. 7. Consider using alternative container build tools or configurations that do not exhibit this behavior until patches are applied. 8. Educate DevOps and security teams about this vulnerability to increase awareness and encourage best practices in container security.