# CVE-2021-31403: Timing side channel vulnerability in UIDL request handler in Vaadin 7 and 8

Source: https://junglewise.ai/threats/cve-2021-31403-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-2021-31403 · Severity: low · CVSS 3.1 · Published 2021-04-19

Timing side channel vulnerability in UIDL request handler in Vaadin 7 and 8

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

## Quick answers

**Is CVE-2021-31403 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2021-31403 being exploited in the wild.

**How severe is CVE-2021-31403?** Low severity, with a CVSS score of 3.1, published 19 April 2021.

**Which products and versions are affected?** com.vaadin:vaadin-bom (Maven) ECOSYSTEM:introduced=7.0.0,fixed=7.7.24; com.vaadin:vaadin-server (Maven) ECOSYSTEM:introduced=7.0.0,fixed=7.7.24.

**Is there a fix for CVE-2021-31403?** Yes. com.vaadin:vaadin-bom (Maven): upgrade to 7.7.24 or later; com.vaadin:vaadin-server (Maven): upgrade to 7.7.24 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2021-31403?** Check whether you run com.vaadin:vaadin-bom (Maven) or com.vaadin:vaadin-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:vaadin-bom (Maven): upgrade to 7.7.24 or later

  ```sh
  # set com.vaadin:vaadin-bom to 7.7.24 in your pom.xml or build.gradle
  ```

- com.vaadin:vaadin-server (Maven): upgrade to 7.7.24 or later

  ```sh
  # set com.vaadin:vaadin-server to 7.7.24 in your pom.xml or build.gradle
  ```


## Affected products

- com.vaadin:vaadin-bom (Maven) ECOSYSTEM:introduced=7.0.0,fixed=7.7.24
- com.vaadin:vaadin-server (Maven) ECOSYSTEM:introduced=7.0.0,fixed=7.7.24

## Identifiers

- CVE-2021-31403
- GHSA-75xc-qvxh-27f8

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