Multiple Kubernetes Sidecar Containers CVE-2019-11255 Unauthorized Access Vulnerability

Description

Multiple Kubernetes Sidecar Containers are prone to an unauthorized access vulnerability. An attacker can exploit this issue to gain unauthorized access and perform unintended actions. This may lead to further attacks.

Technologies Affected

• Kubernetes external-provisioner 0.4.1
• Kubernetes external-provisioner 0.4.2
• Kubernetes external-provisioner 1.0.0
• Kubernetes external-provisioner 1.0.1
• Kubernetes external-provisioner 1.1.0
• Kubernetes external-provisioner 1.2.1
• Kubernetes external-provisioner 1.3.0
• Kubernetes external-resizer 0.1.0
• Kubernetes external-resizer 0.2.0
• Kubernetes external-snapshotter 0.4.0
• Kubernetes external-snapshotter 0.4.1
• Kubernetes external-snapshotter 1.0.0
• Kubernetes external-snapshotter 1.0.1
• Kubernetes external-snapshotter 1.1.0
• Kubernetes external-snapshotter 1.2.1

Recommendations

Block external access at the network boundary, unless external parties require service.
If global access isn’t needed, filter access to the affected computer at the network boundary. Restricting access to only trusted computers and networks might greatly reduce the likelihood of successful exploits.

Run all software as a nonprivileged user with minimal access rights.
Execute all software as a user with minimal privileges. Use additional precautions such as restrictive environments to insulate software that may potentially handle malicious content.

Deploy network intrusion detection systems to monitor network traffic for malicious activity.
Deploy NIDS to detect and block attacks and anomalous activity such as requests containing suspicious URI sequences. Since the webserver may log such requests, review logs regularly.

Updates are available. Please see the references or vendor advisory for more information.