CVE-2021-33604

Reflected cross-site scripting in development mode handler in Vaadin 14, 15-19

Description

URL encoding error in development mode handler in com.vaadin:flow-server versions 2.0.0 through 2.6.1 (Vaadin 14.0.0 through 14.6.1), 3.0.0 through 6.0.9 (Vaadin 15.0.0 through 19.0.8) allows local user to execute arbitrary JavaScript code by opening crafted URL in browser.

Category

2.5
CVSS
Severity: Low
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-2021-33604 vendor advisory
https://github.com/vaadin/flow/pull/11099 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-33604?
CVE-2021-33604 has been scored as a low severity vulnerability.
How to fix CVE-2021-33604?
To fix CVE-2021-33604, 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-2021-33604 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-33604 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-2021-33604?
CVE-2021-33604 affects Vaadin Vaadin, Vaadin flow-server.
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