Source URL: https://www.theregister.com/2024/10/16/critical_kubernetes_image_builder_bug/
Source: Hacker News
Title: Critical default credentials in Kubernetes allows SSH root access
Feedly Summary: Comments
AI Summary and Description: Yes
Summary: The text discusses a critical security vulnerability in the Kubernetes Image Builder, which can allow unauthorized SSH access to virtual machines through default credentials. It highlights the potential risks associated with VM images built using specific providers and emphasizes the importance of upgrading to a secure version for mitigation.
Detailed Description:
The analysis reveals a significant security issue within the Kubernetes Image Builder, impacting structures within cloud infrastructure and virtualization security. Here are the major points:
– **Vulnerability Identification (CVE-2024-9486)**:
– A critical bug in Kubernetes Image Builder allows unauthorized SSH access to VMs due to default credentials being active during the image build process.
– This flaw has been rated 9.8 out of 10 on the CVSS severity scale, indicating a high risk of exploitation.
– **Affected Systems**:
– VM images built with the Proxmox provider are at greatest risk due to the retention of default credentials.
– Other providers affected include Nutanix, OVA, QEMU, and raw providers, but these instances have a lower severity rating of 6.3 under a different CVE tracker (CVE-2024-9594).
– **Exploitation Conditions**:
– Successful exploitation of CVE-2024-9594 requires an attacker to access the VM where the image build takes place and modify the image during the building phase.
– This limitation reduces the attack window, as Nutanix, OVA, and QEMU disable the default credentials post-build.
– **Mitigation Steps**:
– Users are advised to upgrade to Image Builder version 0.1.38 or later, which implements a safety feature by generating a random password for the builder account and disabling it after the build process.
– A temporary workaround involves manually disabling the builder account before an upgrade.
This vulnerability represents a significant concern for cloud and infrastructure security professionals, reinforcing the need for rigorous image management practices, regular updates, and awareness of default credentials during configuration processes. Ongoing monitoring and vulnerability assessments are advisable for organizations utilizing Kubernetes and related infrastructure to prevent potential exploitation.