CVE-2021-31404 Timing side channel vulnerability in UIDL request handler in Vaadin 10, 11-14, and 15-18

What is CVE-2021-31404?

CVE-2021-31404 is a medium-severity vulnerability in Vaadin, published on 23 Apr 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Non-constant-time comparison of CSRF tokens in UIDL request handler in com.vaadin:flow-server versions 1.0.0 through 1.0.13 (Vaadin 10.0.0 through 10.0.16), 1.1.0 prior to 2.0.0 (Vaadin 11 prior to 14), 2.0.0 through 2.4.6 (Vaadin 14.0.0 through 14.4.6), 3.0.0 prior to 5.0.0 (Vaadin 15 prior to 18), and 5.0.0 through 5.0.2 (Vaadin 18.0.0 through 18.0.5) allows attacker to guess a security token via timing attack.

Weakness: CWE-203, CWE-208

Which versions are affected by CVE-2021-31404?

6 open source packages ship an affected version, including com.vaadin:flow-server. It affects 2 products.

Products include Vaadin Flow, Vaadin Vaadin.

How do I fix CVE-2021-31404?

Upgrade com.vaadin:flow-server to a fixed version for your release line: 1.0.14, 2.4.7 or 5.0.3.

Is CVE-2021-31404 being exploited?

There is no known exploitation of CVE-2021-31404 in the wild and no public exploit code.

Other vulnerabilities in Vaadin

• CVE-2021-31407 Server classes and resources exposure in OSGi applications using Vaadin 12-14 and 19 High 8.6
• CVE-2021-31405 Regular expression denial of service (ReDoS) in EmailField component in Vaadin 14 and 15-17 High 7.5
• CVE-2021-31411 Insecure temporary directory usage in frontend build functionality of Vaadin 14 and 15-19 Medium 6.3
• CVE-2021-31408 Server session is not invalidated when logout() helper method of Authentication module is used in Vaadin 18-19 Medium 6.3
• CVE-2019-25027 Reflected cross-site scripting in default RouteNotFoundError view in Vaadin 10 and 11-13 Medium 6.1

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-xwg3-qrcg-w9x6.