CVE-2021-31408

Name: CVE-2021-31408
Creator: NVD / NIST
Published: 2021-04-23T17:15:08.26+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.1/10EPSS 0.32%

Last modified Jun 17, 2026

CVE-2021-31408 is a high-severity vulnerability rated 7.1/10 on the CVSS scale. Authentication.logout() helper in com.vaadin:flow-client versions 5.0.0 prior to 6.0.0 (Vaadin 18), and 6.0.0 through 6.0.4 (Vaadin 19.0.0 through 19.0.3) uses incorrect HTTP method, which, in combination with Spring Security CSRF protection, allows local attackers to access Fusion endpoints after the user attempted to log out.. EPSS estimates a 0.32% chance of exploitation in the next 30 days.

Description

Authentication.logout() helper in com.vaadin:flow-client versions 5.0.0 prior to 6.0.0 (Vaadin 18), and 6.0.0 through 6.0.4 (Vaadin 19.0.0 through 19.0.3) uses incorrect HTTP method, which, in combination with Spring Security CSRF protection, allows local attackers to access Fusion endpoints after the user attempted to log out.

Metrics

CVSS 3.1

7.1/10

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

EPSS Probability

0.32%

23.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Vaadin	Flow	>= 5.0.0, < 6.0.0
Vaadin	Flow	>= 6.0.0, < 6.0.5
Vaadin	Vaadin	>= 19.0.0, < 19.0.4
Vaadin	Vaadin	18.0.0

References

https://github.com/vaadin/flow/pull/10577Patch, Third Party Advisory
https://vaadin.com/security/cve-2021-31408Vendor Advisory
https://github.com/vaadin/flow/pull/10577Patch, Third Party Advisory
https://vaadin.com/security/cve-2021-31408Vendor Advisory

Timeline

Published: Apr 23, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-31408?

How severe is CVE-2021-31408?

CVE-2021-31408 has a CVSS score of 7.1/10 (HIGH severity). The EPSS model estimates a 0.32% probability of exploitation in the next 30 days.

How do I fix CVE-2021-31408?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-31408?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST