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

Source: https://junglewise.ai/threats/cve-2021-31404-timing-side-channel-vulnerability-in-uidl-request-handler-in  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-04-19  
License: CC BY 4.0 with a link back

CVE-2021-31404 · Severity: low · CVSS 3.1 · Published 2021-04-19

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

Technologies: [com.vaadin:flow-server (Maven)](https://junglewise.ai/threats/technologies/com-vaadin-flow-server). Vendors: [Maven](https://junglewise.ai/threats/vendors/maven).

## Quick answers

**Is CVE-2021-31404 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2021-31404 being exploited in the wild.

**How severe is CVE-2021-31404?** Low severity, with a CVSS score of 3.1, published 19 April 2021.

**Which products and versions are affected?** com.vaadin:flow-server (Maven) ECOSYSTEM:introduced=1.0.0,fixed=1.0.14.

**Is there a fix for CVE-2021-31404?** Yes. com.vaadin:flow-server (Maven): upgrade to 1.0.14 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2021-31404?** Check whether you run com.vaadin:flow-server (Maven) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- com.vaadin:flow-server (Maven): upgrade to 1.0.14 or later

  ```sh
  # set com.vaadin:flow-server to 1.0.14 in your pom.xml or build.gradle
  ```


## Affected products

- com.vaadin:flow-server (Maven) ECOSYSTEM:introduced=1.0.0,fixed=1.0.14

## Identifiers

- CVE-2021-31404
- GHSA-xwg3-qrcg-w9x6

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