CVE-2025-57849 is a security vulnerability identified in Red Hat Fuse 7 container images, where the /etc/passwd file is created with group-writable permissions during the image build process. This misconfiguration allows any user who has command execution capabilities inside the container and is a member of the root group to modify the /etc/passwd file. By doing so, the attacker can add new user entries with arbitrary user IDs, including UID 0, effectively granting themselves root-level privileges within the container environment. The vulnerability arises from improper file permission settings that violate the principle of least privilege, enabling privilege escalation from a non-root user to root within the container. Exploitation requires that the attacker already have some level of access inside the container and be part of the root group, which limits the attack surface but still poses a significant risk in multi-tenant or shared container environments. The CVSS v3.1 score of 6.4 reflects a medium severity, considering the attack vector is local (AV:L), requires high privileges (PR:H), and no user interaction (UI:N). The impact on confidentiality, integrity, and availability is high because gaining root privileges inside the container can lead to unauthorized data access, modification, and potential disruption of containerized services. No known exploits have been reported in the wild as of the publication date, but the vulnerability demands attention due to the widespread use of Red Hat Fuse in enterprise middleware and integration solutions. The issue can be mitigated by correcting the file permissions during image build, restricting root group membership, and enforcing container security best practices.

The primary impact of CVE-2025-57849 is the potential for privilege escalation within containerized environments running Red Hat Fuse 7. An attacker who already has command execution inside the container and is a member of the root group can escalate privileges to root by modifying the /etc/passwd file. This can lead to full control over the container, allowing unauthorized access to sensitive data, modification of application behavior, and disruption of services. In multi-tenant environments or shared infrastructure, this could facilitate lateral movement or compromise of other containers or host systems if container isolation is weak. The vulnerability undermines container security assumptions and could be leveraged in complex attack chains. Although exploitation requires some pre-existing access and group membership, the impact on confidentiality, integrity, and availability within the container is severe. Organizations relying on Red Hat Fuse 7 containers for critical middleware and integration workloads face risks of data breaches, service outages, and compliance violations if this vulnerability is exploited.

To mitigate CVE-2025-57849, organizations should take the following specific actions: 1) Rebuild affected Red Hat Fuse 7 container images ensuring that the /etc/passwd file is created with secure, non-group-writable permissions during the build process. 2) Audit and restrict membership of the root group within containers to the minimum necessary users, ideally avoiding non-root users in this group. 3) Implement container runtime security policies that prevent unauthorized modification of critical system files such as /etc/passwd, using tools like SELinux, AppArmor, or seccomp profiles. 4) Employ container image scanning and continuous security validation to detect insecure file permissions and privilege escalation risks before deployment. 5) Use least privilege principles for container users and avoid running containers with elevated privileges unless absolutely required. 6) Monitor container logs and behavior for suspicious activities indicative of privilege escalation attempts. 7) Stay updated with Red Hat security advisories and apply patches or updated images as they become available. These targeted measures go beyond generic advice by focusing on build-time image hygiene, group membership controls, and runtime enforcement.