Security readout for executives and security teams
Plain-English summary
A specially prepared container can make CRI-O consume excessive host memory when it requests a nonexistent user and contains an unusually large /etc/passwd file. The resulting out-of-memory condition can terminate applications and disrupt other pods or services on the same host. The supplied sources rate this as medium severity.
Executive priority
Treat this as a moderate operational-resilience issue. Prioritize internet-facing, multi-tenant, or less-trusted workload environments because successful abuse may affect neighboring services on the same host. Confirm exposure promptly, then follow Red Hat’s supported remediation guidance. No active exploitation evidence is supplied.
Technical view
CRI-O reads the container’s entire /etc/passwd file into memory while attempting to create a runAsUser identity that does not exist. An excessively large file can exhaust memory, producing a host-level denial of service. This is classified as CWE-770, with CVSS 3.1 score 5.7. Specific affected versions are not supplied.
Likely exposure
Exposure is indicated for Red Hat OpenShift Container Platform 4 deployments using affected CRI-O or openshift/ose-rhel-coreos-9 components. Practical risk is higher where less-trusted users can submit workloads, influence container images, or set securityContext.runAsUser. Exact affected versions are not provided.
Exploitation context
The supplied record does not report known active exploitation, and CVE-2025-4437 is not identified as a KEV entry. Exploitation requires a container combining a nonexistent runAsUser identity with an excessively large /etc/passwd file, potentially causing memory exhaustion on its host.
Researcher notes
The vulnerable path involves unbounded memory consumption while CRI-O processes the complete container /etc/passwd file for a nonexistent runAsUser. Scope remains unchanged and impact is availability only under the supplied CVSS vector. Version boundaries, patched releases, and confirmed exploitation are absent from the bundle.
Mitigation direction
- Check Red Hat guidance for affected versions, patches, and supported remediation.
- Prioritize remediation on clusters accepting workloads or images from less-trusted users.
- Review admission controls governing container images and securityContext.runAsUser settings.
- Monitor node memory pressure and unexpected out-of-memory application terminations.
Validation and detection
- Inventory OpenShift Container Platform 4 clusters and their CRI-O and RHEL CoreOS package versions.
- Compare installed versions with Red Hat’s current CVE and Bugzilla guidance.
- Identify workloads specifying runAsUser values absent from their container account databases.
- Review container images for unexpectedly large /etc/passwd files.
- Examine node monitoring for memory spikes, OOM events, and correlated pod disruption.
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-770: 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 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-2025-4437 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
- 5.7 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/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.
SSVC decision data
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:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H2.13.6redhatVulnerability scoring details
Base CVSS 3.1 score
5.7MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- Source timelineredhat
Made public.
- Source timelineredhat
Reported to Red Hat.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://access.redhat.com/security/cve/CVE-2025-4437CVE reference, redhat · vdb-entry, x_refsource_REDHAT
- RHBZ#2375084CVE reference, redhat · 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.
Allocation of Resources Without Limits or Throttling
Allocation of Resources Without Limits or Throttling represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.