A container privilege escalation flaw exists in certain Red Hat Fuse 7 images. The build process creates /etc/passwd with group-writable permissions (CWE-276). As a result, a non-root user who can execute commands inside the container and belongs to the root group can modify /etc/passwd. By creating a new entry with an arbitrary UID, the attacker can add a UID 0 account and thereby gain full root privileges within the container, compromising confidentiality, integrity, and availability.

The vulnerability affects Red Hat Fuse 7 container images, identified by the CPE cpe:/a:redhat:jboss_fuse:7. No specific version numbers were supplied, so any Fuse 7 image built from the indicated sources is potentially vulnerable. Red Hat publishes advisories at https://access.redhat.com/security/cve/CVE-2025-57849.

The CVSS base score is 6.4, indicating moderate risk. The EPSS score is reported as less than 1%, signifying low exploitation probability. The vulnerability is not listed in CISA’s KEV catalog. Exploitation requires an attacker who can execute code inside the container and is a member of the root group; the likely attack vector is local container privilege escalation. Once the attacker creates a UID 0 entry, they can run arbitrary commands with root privileges within the container, potentially affecting the host if privileged containers or breakout is feasible.