Headline
GHSA-cm9x-c3rh-7rc4: CRI-O vulnerable to /etc/passwd tampering resulting in Privilege Escalation
Impact
It is possible to craft an environment variable with newlines to add entries to a container’s /etc/passwd. It is possible to circumvent admission validation of username/UID by adding such an entry.
Note: because the pod author is in control of the container’s /etc/passwd, this is not considered a new risk factor. However, this advisory is being opened for transparency and as a way of tracking fixes.
Patches
1.26.0 will have the fix. More patches will be posted as they’re available.
Workarounds
Additional security controls like SELinux should prevent any damage a container is able to do with root on the host. Using SELinux is recommended because this class of attack is already possible by manually editing the container’s /etc/passwd
References
Impact
It is possible to craft an environment variable with newlines to add entries to a container’s /etc/passwd. It is possible to circumvent admission validation of username/UID by adding such an entry.
Note: because the pod author is in control of the container’s /etc/passwd, this is not considered a new risk factor. However, this advisory is being opened for transparency and as a way of tracking fixes.
Patches
1.26.0 will have the fix. More patches will be posted as they’re available.
Workarounds
Additional security controls like SELinux should prevent any damage a container is able to do with root on the host. Using SELinux is recommended because this class of attack is already possible by manually editing the container’s /etc/passwd
References****References
- GHSA-cm9x-c3rh-7rc4
- cri-o/cri-o#6450
Related news
A vulnerability was found in cri-o. This issue allows the addition of arbitrary lines into /etc/passwd by use of a specially crafted environment variable.
Red Hat Security Advisory 2023-1504-01 - Red Hat OpenShift Container Platform is Red Hat's cloud computing Kubernetes application platform solution designed for on-premise or private cloud deployments. This advisory contains the container images for Red Hat OpenShift Container Platform 4.11.34.
Red Hat OpenShift Container Platform release 4.11.34 is now available with updates to packages and images that fix several bugs and add enhancements. This release includes a security update for Red Hat OpenShift Container Platform 4.11. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original. Related CVEs: * CVE-2022-4318: A vulnerability was found in cri-o. This issue allows the addition of arbitrary lines into /etc/passwd by use of a specially crafted environment variable.