CVE-2019-11253: Kubernetes API Server JSON/YAML parsing vulnerable to resource exhaustion attack
A flaw was found kubernetes. The parsing of YAML manifests by the Kubernetes API server could lead to a denial-of-service attack leaving it vulnerable to an instance of a "billion laughs" attack. The highest threat from this vulnerability is to system availability.
Other sources
Improper input validation in the Kubernetes API server in versions v1.0-1.12 and versions prior to v1.13.12, v1.14.8, v1.15.5, and v1.16.2 allows authorized users to send malicious YAML or JSON payloads, causing the API server to consume excessive CPU or memory, potentially crashing and becoming unavailable. Prior to v1.14.0, default RBAC policy authorized anonymous users to submit requests that could trigger this vulnerability. Clusters upgraded from a version prior to v1.14.0 keep the more permissive policy by default for backwards compatibility.
The parsing of YAML manifests by the Kubernetes API server could lead to a denial-of-service attack against a cluster’s Kubernetes API service, therefore leaving it vulnerable to an instance of a “billion laughs” attack.
Upstream Issue:
https://github.com/kubernetes/kubernetes/issues/83253
Reference:
https://www.stackrox.com/post/2019/09/protecting-kubernetes-api-against-cve-2019-11253-billion-laughs-attack/
— Red Hat
Affected Software
Event History
Parent advisories
This vulnerability appears in the following advisories.
Frequently Asked Questions
What is CVE-2019-11253?
CVE-2019-11253 is a vulnerability in Kubernetes that allows authorized users to send malicious YAML or JSON payloads, causing the API server to consume excessive CPU or memory, potentially crashing and becoming unresponsive.
How does CVE-2019-11253 impact Kubernetes API server?
CVE-2019-11253 can result in the Kubernetes API server consuming excessive CPU or memory, potentially leading to crash and unresponsiveness.
What is the severity level of CVE-2019-11253?
CVE-2019-11253 has a severity level of 7.5 (high).
Which versions of Kubernetes are affected by CVE-2019-11253?
Versions v1.0-1.12 and versions prior to v1.13.12, v1.14.8, v1.15.5, and v1.16.2 are affected by CVE-2019-11253.
How can I fix CVE-2019-11253?
To fix CVE-2019-11253, ensure that you update your Kubernetes version to at least v1.13.12, v1.14.8, v1.15.5, or v1.16.2.