CVE-2021-25745 : What You Need to Know
Learn about CVE-2021-25745, a critical security flaw in Kubernetes ingress-nginx that allows unauthorized access to controller credentials, potentially compromising all cluster secrets. Find out how to mitigate this vulnerability.
A security issue was discovered in Kubernetes ingress-nginx where a user can exploit a vulnerability to access the credentials of the ingress-nginx controller, potentially compromising all secrets in the cluster.
Understanding CVE-2021-25745
This CVE refers to a vulnerability found in Kubernetes ingress-nginx that allows unauthorized users to obtain sensitive information.
What is CVE-2021-25745?
The security issue in ingress-nginx enables users with certain permissions to extract credentials from the controller, granting access to all secrets in the cluster.
The Impact of CVE-2021-25745
This vulnerability poses a high severity risk, with a base CVSS score of 7.6. It affects the confidentiality of data and could lead to unauthorized access to critical information.
Technical Details of CVE-2021-25745
The vulnerability stems from improper validation of input, allowing malicious users to manipulate the path fields of Ingress objects to access controller credentials.
Vulnerability Description
Users with the ability to create or update ingress objects can exploit the spec.rules[].http.paths[].path field to extract sensitive credentials.
Affected Systems and Versions
Kubernetes ingress-nginx versions prior to 1.2.0 are impacted by this security flaw.
Exploitation Mechanism
By manipulating the path field in Ingress objects, attackers can obtain the credentials of the ingress-nginx controller in the default configuration.
Mitigation and Prevention
Addressing CVE-2021-25745 requires immediate action to secure Kubernetes deployments and prevent unauthorized access to sensitive data.
Immediate Steps to Take
Users should update Kubernetes ingress-nginx to version 1.2.0 or higher to mitigate the vulnerability. Additionally, review and restrict user permissions to minimize potential exploitation.
Long-Term Security Practices
Implement secure coding practices, regular security audits, and access control measures to bolster the overall security posture of Kubernetes deployments.
Patching and Updates
Stay informed about security advisories and promptly apply patches released by Kubernetes to address known vulnerabilities.