CVE-2021-31406

Timing side channel vulnerability in endpoint request handler in Vaadin 15-19

Description

Non-constant-time comparison of CSRF tokens in endpoint request handler in com.vaadin:flow-server versions 3.0.0 through 5.0.3 (Vaadin 15.0.0 through 18.0.6), and com.vaadin:fusion-endpoint version 6.0.0 (Vaadin 19.0.0) allows attacker to guess a security token for Fusion endpoints via timing attack.

Categories

4.0
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.05%
Vendor Advisory vaadin.com
Affected: Vaadin Vaadin
Affected: Vaadin flow-server
Published at:
Updated at:

References

Link Tags
https://vaadin.com/security/cve-2021-31406 vendor advisory
https://github.com/vaadin/flow/pull/10157 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-31406?
CVE-2021-31406 has been scored as a medium severity vulnerability.
How to fix CVE-2021-31406?
To fix CVE-2021-31406, 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-2021-31406 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-31406 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-2021-31406?
CVE-2021-31406 affects Vaadin Vaadin, Vaadin flow-server.
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