Security readout for executives and security teams
Plain-English summary
CVE-2025-57851 affects certain Red Hat Multicluster Engine for Kubernetes container images. A file permission mistake can let someone who already has command execution inside the container become root inside that container. This is not a remote, unauthenticated issue, but it matters where these images run in sensitive cluster-management environments.
Executive priority
Treat as a targeted container hardening issue, not an internet-scale emergency. Prioritize if MCE manages important clusters or if operators, CI jobs, or compromised workloads can execute commands inside these containers.
Technical view
Affected MCE images create /etc/passwd with group-writable permissions. Under certain conditions, a non-root attacker inside the container who is in the root group can modify /etc/passwd and add a UID 0 user, gaining root privileges in the container. CVSS is 6.4, with local attack vector, high complexity, and high privileges required.
Likely exposure
Exposure is most likely in environments running the listed Red Hat Multicluster Engine for Kubernetes images: agent-service-rhel8, assisted-service-8-rhel8, or assisted-service-9-rhel9. The source bundle does not identify exact affected versions.
Exploitation context
No active exploitation is indicated by KEV or the provided sources. Exploitation requires prior command execution inside an affected container and specific user/group conditions. Impact is root access within the container, which may be more serious depending on container privileges and cluster configuration.
Researcher notes
The key missing detail is affected version range and fixed build information. Analysis should focus on image provenance, file permissions in built images, runtime user/group configuration, and whether container-root could translate into broader cluster impact in the local deployment.
Mitigation direction
- Check Red Hat guidance for fixed images or official workarounds.
- Inventory deployments using the affected MCE image names.
- Limit interactive shell and exec access to these containers.
- Run containers with least privilege and avoid unnecessary root-group membership.
- Prioritize replacement of affected images when vendor-fixed builds are available.
Validation and detection
- Identify running workloads using the affected MCE image names.
- Check whether /etc/passwd is group-writable inside affected containers.
- Review container users and group membership for root-group exposure.
- Confirm whether Red Hat lists your deployed build as affected.
- Verify updated images no longer have group-writable /etc/passwd.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-276: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupPrivilege behavior lookup
The CVE wording references privilege impact, so privilege escalation and authorization behavior review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupContainer behavior lookup
The affected technology mentions containers, so container-specific ATT&CK technique review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2025-57851 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.4 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H0.55.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.4MediumVector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://access.redhat.com/security/cve/CVE-2025-57851CVE reference · vdb-entry, x_refsource_REDHAT
- RHBZ#2391104CVE reference · issue-tracking, x_refsource_REDHAT
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Incorrect Default Permissions
Incorrect Default Permissions represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.