CVE-2021-31408 : Security Advisory and Response
Learn about CVE-2021-31408, a medium severity vulnerability in Vaadin 18-19's Authentication.logout() method. Understand the impact, affected versions, and mitigation steps.
A security vulnerability, tracked as CVE-2021-31408, has been identified in Vaadin versions 18 and 19. This CVE, published on April 20, 2021, highlights an issue with the Authentication.logout() helper method in com.vaadin:flow-client, allowing local attackers to access Fusion endpoints post-logout.
Understanding CVE-2021-31408
This section will delve into the specifics of the CVE-2021-31408 vulnerability.
What is CVE-2021-31408?
The vulnerability lies in the improper usage of the HTTP method by the Authentication.logout() helper in Vaadin versions 18 and 19. Attackers can exploit this issue in combination with Spring Security CSRF protection to gain unauthorized access to Fusion endpoints after a user logs out.
The Impact of CVE-2021-31408
With a CVSS base score of 6.3, this vulnerability poses a medium severity risk. It can lead to high confidentiality and integrity impacts without requiring any special privileges, thus affecting the security of the affected systems.
Technical Details of CVE-2021-31408
Let's explore the technical details related to CVE-2021-31408.
Vulnerability Description
The vulnerability allows local attackers to access Fusion endpoints due to the incorrect HTTP method used in the Authentication.logout() helper of Vaadin version 18 and 19.
Affected Systems and Versions
Vaadin versions 18.0.0 to 19.0.3 are impacted, specifically com.vaadin:flow-client versions 5.0.0 to 6.0.4.
Exploitation Mechanism
Attackers exploit the incorrect HTTP method, coupled with Spring Security CSRF protection, to gain unauthorized access to Fusion endpoints post-user logout.
Mitigation and Prevention
To address CVE-2021-31408, immediate steps and long-term security practices can be implemented.
Immediate Steps to Take
Users are advised to update affected Vaadin versions and apply relevant patches promptly. Additionally, reviewing and adjusting security configurations can mitigate the risk.
Long-Term Security Practices
Implementing proper session management, security headers, and regular security assessments can enhance the overall security posture and prevent similar vulnerabilities.
Patching and Updates
Stay informed about security advisories from Vaadin and promptly apply patches and updates to secure the systems against known vulnerabilities.