Security Experts:

Connect with us

Hi, what are you looking for?



Vulnerability in Kubernetes Allows Access to Custom Resources

A vulnerability addressed this week in the Kubernetes container orchestration system could allow users to read, modify or delete cluster-wide custom resources.

A vulnerability addressed this week in the Kubernetes container orchestration system could allow users to read, modify or delete cluster-wide custom resources.

Tracked as CVE-2019-11247, the security flaw is due to an API server providing access to custom resources via wrong scope. Specifically, users are granted access to a cluster-scoped custom resource if the request is made as if the resource were namespaced.

“Authorizations for the resource accessed in this manner are enforced using roles and role bindings within the namespace,” Kubernetes’ Joel Smith explains

Due to this vulnerability, a user with access only to a resource in one namespace could create, view update or delete the cluster-scoped resource (according to their namespace role privileges).

According to StackRox, clusters that are not using Custom Resource Definitions (CRDs) are not affected by the bug. However, with CRDs being a critical component of many Kubernetes-native projects, many users are likely impacted. 

Clusters running without Kubernetes RBAC aren’t impacted either, but not using Kubernetes RBAC creates an even greater risk than this vulnerability does. 

“Although CVE-2019-11247 has been assigned a medium-severity CVSS score, it poses an especially serious threat when custom resources are used to manage functionality related to cluster or application security,” StackRox notes

The second security issue is tracked as CVE-2019-11249 and consists of incomplete fixes for two other vulnerabilities, namely CVE-2019-1002101 and CVE-2019-11246, and kubectl cp potential directory traversal. 

“This vulnerability allows a malicious container to cause a file to be created or replaced on the client computer when the client uses the kubectl cp operation. The vulnerability is a client-side defect and requires user interaction to be exploited,” Smith explains. 

All users are advised to upgrade all Kubernetes clusters and kubectl clients to a patched version, namely Kubernetes 1.13.9, 1.14.5, and 1.15.2. 

Related: Serious Path Traversal Flaw Found in Kubernetes

Related: Critical Privilege Escalation Flaw Patched in Kubernetes

Written By

Ionut Arghire is an international correspondent for SecurityWeek.

Click to comment

Daily Briefing Newsletter

Subscribe to the SecurityWeek Email Briefing to stay informed on the latest threats, trends, and technology, along with insightful columns from industry experts.

Join this webinar to learn best practices that organizations can use to improve both their resilience to new threats and their response times to incidents.


Join this live webinar as we explore the potential security threats that can arise when third parties are granted access to a sensitive data or systems.


Expert Insights

Related Content


Less than a week after announcing that it would suspended service indefinitely due to a conflict with an (at the time) unnamed security researcher...

Risk Management

The supply chain threat is directly linked to attack surface management, but the supply chain must be known and understood before it can be...


Apple has released updates for macOS, iOS and Safari and they all include a WebKit patch for a zero-day vulnerability tracked as CVE-2023-23529.


Patch Tuesday: Microsoft warns vulnerability (CVE-2023-23397) could lead to exploitation before an email is viewed in the Preview Pane.

Application Security

Drupal released updates that resolve four vulnerabilities in Drupal core and three plugins.

Cloud Security

VMware vRealize Log Insight vulnerability allows an unauthenticated attacker to take full control of a target system.

IoT Security

Lexmark warns of a remote code execution (RCE) vulnerability impacting over 120 printer models, for which PoC code has been published.

Application Security

A CSRF vulnerability in the source control management (SCM) service Kudu could be exploited to achieve remote code execution in multiple Azure services.