CVE-2025-4437 — cri-o
MEDIUMCVE-2025-4437 is a medium-severity (CVSS 5.7) CWE-770 vulnerability in github.com/cri-o/cri-o. The records list no fixed version yet; check the vendor advisory below and apply the mitigations in the meantime.
CRI-O has Potential High Memory Consumption from File Read
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-4437.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
github.com/cri-o/cri-oReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
There's a vulnerability in the CRI-O application where when container is launched with securityContext.runAsUser specifying a non-existent user, CRI-O attempts to create the user, reading the container's entire /etc/passwd file into memory. If this file is excessively large, it can cause the a high memory consumption leading applications to be killed due to out-of-memory. As a result a denial-of-service can be achieved, possibly disrupting other pods and services running in the same host.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/cri-o/cri-o | all versions | No fix |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/cri-o/cri-o, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
The records we use list no patched version of github.com/cri-o/cri-o for CVE-2025-4437. Check the maintainer's advisory, and where your build allows, override or pin the dependency away from the vulnerable range.
Mitigate without a patch
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This vulnerability was rated as Moderate by the Red Hat's Product Security team as it requires the attacker to own an account with minimal privileges to create pods using the CRI-O utility.
As for now there's no available mitigation for this flaw.Source: Red Hat security advisory for CVE-2025-4437 (CC BY 4.0)
Frequently Asked Questions
Is CVE-2025-4437 in your dependencies?
Find it across Go, including transitive dependencies.