Description
A container privilege escalation flaw was found in certain Multicluster Engine for Kubernetes images. This issue stems from the /etc/passwd file being created with group-writable permissions during build time. In certain conditions, an attacker who can execute commands within an affected container, even as a non-root user, can leverage their membership in the root group to modify the /etc/passwd file. This could allow the attacker to add a new user with any arbitrary UID, including UID 0, leading to full root privileges within the container.
Affected products
redhat: advanced cluster management for kubernetes
References2
- access.redhat.com/security/cve/CVE-2025-57851 Vendor Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2391104 Issue TrackingVendor Advisory
Metrics
- CVSS 3.1
-
6.7
MEDIUM
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 2 · as of 12 November 2026
- CWE
- CWE-276
Could this be exploited in your environment?
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