# CVE-2025-57851: Red Hat Multicluster Engine for Kubernetes privilege escalation in /etc/passwd

Source: https://junglewise.ai/threats/cve-2025-57851-red-hat-multicluster-engine-for-kubernetes-privilege-escalation  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-08. Updated: 2026-07-24  
License: CC BY 4.0 with a link back

CVE-2025-57851 · Severity: medium · CVSS 6.4 · Published 2026-04-08

A security flaw was found in certain Red Hat Multicluster Engine for Kubernetes container images. This vulnerability allows a user who already has limited access to a container to gain full administrative (root) control over that container. This could lead to unauthorized access to sensitive data or the ability to disrupt services running within the affected container environment.

Technologies: [Redhat Advanced Cluster Management For Kubernetes](https://junglewise.ai/threats/technologies/advanced-cluster-management-for-kubernetes). Vendors: [Redhat](https://junglewise.ai/threats/vendors/redhat).

## Quick answers

**Is CVE-2025-57851 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-57851 being exploited in the wild.

**How severe is CVE-2025-57851?** Medium severity, with a CVSS score of 6.4, published 8 April 2026.

**Which products and versions are affected?** Red Hat Multicluster Engine for Kubernetes unspecified.

**Is there a fix for CVE-2025-57851?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2025-57851 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2025-57851?** Check whether you run Redhat Advanced Cluster Management For Kubernetes. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A privilege escalation vulnerability exists in Red Hat Multicluster Engine for Kubernetes images due to incorrect default permissions (CWE-276). The /etc/passwd file is created with group-writable permissions during the image build process. An attacker who can execute commands within the container and is a member of the root group can modify /etc/passwd to add a new user with UID 0. This allows the attacker to escalate from a non-root user to full root privileges within the container environment. The attack requires local access and high privileges (membership in the root group) to succeed.

## Affected products

- Red Hat Multicluster Engine for Kubernetes unspecified

## Timeline

- 2025-08-26: disclosed: Initial report in Red Hat Bugzilla
- 2026-04-08: advisory: NVD publication date

## References

- [https://access.redhat.com/downloads/content/package-browser/](https://access.redhat.com/downloads/content/package-browser/)
- [https://access.redhat.com/security/cve/CVE-2025-57851](https://access.redhat.com/security/cve/CVE-2025-57851)
- [https://bugzilla.redhat.com/show_bug.cgi?id=2391104](https://bugzilla.redhat.com/show_bug.cgi?id=2391104)

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