CVE-2020-8557

Name: CVE-2020-8557
Creator: NVD / NIST
Published: 2020-07-23T17:15:12.513+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.5/10EPSS 0.50%

Last modified Jun 17, 2026

CVE-2020-8557 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. The Kubernetes kubelet component in versions 1.1-1.16.12, 1.17.0-1.17.8 and 1.18.0-1.18.5 do not account for disk usage by a pod which writes to its own /etc/hosts file. The /etc/hosts file mounted in a pod by kubelet is not included by the kubelet eviction manager when calculating ephemeral storage usage by a pod. EPSS estimates a 0.50% chance of exploitation in the next 30 days.

Description

The Kubernetes kubelet component in versions 1.1-1.16.12, 1.17.0-1.17.8 and 1.18.0-1.18.5 do not account for disk usage by a pod which writes to its own /etc/hosts file. The /etc/hosts file mounted in a pod by kubelet is not included by the kubelet eviction manager when calculating ephemeral storage usage by a pod. If a pod writes a large amount of data to the /etc/hosts file, it could fill the storage space of the node and cause the node to fail.

Metrics

CVSS 3.1

5.5/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.50%

39.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Kubernetes	Kubernetes	< 1.16.13
Kubernetes	Kubernetes	>= 1.17.0, < 1.17.9
Kubernetes	Kubernetes	>= 1.18.0, < 1.18.6

References

https://github.com/kubernetes/kubernetes/issues/93032Issue Tracking, Patch, Third Party Advisory
https://groups.google.com/g/kubernetes-security-announce/c/cB_JUsYEKyY/m/vVSO61AhBwAJMailing List, Third Party Advisory
https://security.netapp.com/advisory/ntap-20200821-0002/Third Party Advisory
https://github.com/kubernetes/kubernetes/issues/93032Issue Tracking, Patch, Third Party Advisory
https://groups.google.com/g/kubernetes-security-announce/c/cB_JUsYEKyY/m/vVSO61AhBwAJMailing List, Third Party Advisory
https://security.netapp.com/advisory/ntap-20200821-0002/Third Party Advisory

Timeline

Published: Jul 23, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-8557?

How severe is CVE-2020-8557?

CVE-2020-8557 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.50% probability of exploitation in the next 30 days.

How do I fix CVE-2020-8557?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-8557?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST