CVE-2021-25748

Ingress-nginx `path` sanitization can be bypassed with newline character

Description

A security issue was discovered in ingress-nginx where a user that can create or update ingress objects can use a newline character to bypass the sanitization of the `spec.rules[].http.paths[].path` field of an Ingress object (in the `networking.k8s.io` or `extensions` API group) to obtain the credentials of the ingress-nginx controller. In the default configuration, that credential has access to all secrets in the cluster.

Category

7.6
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.03%
Vendor Advisory github.com Vendor Advisory google.com
Affected: Kubernetes Kubernetes ingress-nginx
Published at:
Updated at:

References

Link Tags
https://groups.google.com/g/kubernetes-security-announce/c/avaRYa9c7I8 mailing list vendor advisory mitigation
https://github.com/kubernetes/ingress-nginx/issues/8686 issue tracking vendor advisory mitigation

Frequently Asked Questions

What is the severity of CVE-2021-25748?
CVE-2021-25748 has been scored as a high severity vulnerability.
How to fix CVE-2021-25748?
To fix CVE-2021-25748, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-25748 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-25748 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-25748?
CVE-2021-25748 affects Kubernetes Kubernetes ingress-nginx.
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