# CVE-2021-21424: Prevent user enumeration using Guard or the new Authenticator-based Security

Source: https://junglewise.ai/threats/cve-2021-21424-prevent-user-enumeration-using-guard-or-the-new-authenticator  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2021-05-13  
License: CC BY 4.0 with a link back

CVE-2021-21424 · Severity: low · CVSS 3.1 · Published 2021-05-13

Prevent user enumeration using Guard or the new Authenticator-based Security

Technologies: [symfony/security (Packagist)](https://junglewise.ai/threats/technologies/symfony-security), [symfony/security-core (Packagist)](https://junglewise.ai/threats/technologies/symfony-security-core), [symfony/security-http (Packagist)](https://junglewise.ai/threats/technologies/symfony-security-http), [symfony/symfony (Packagist)](https://junglewise.ai/threats/technologies/symfony-symfony). Vendors: [Packagist](https://junglewise.ai/threats/vendors/packagist).

## Quick answers

**Is CVE-2021-21424 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2021-21424 being exploited in the wild.

**How severe is CVE-2021-21424?** Low severity, with a CVSS score of 3.1, published 13 May 2021.

**Which products and versions are affected?** lexik/jwt-authentication-bundle (Packagist) ECOSYSTEM:introduced=2.0.0,fixed=2.10.7; symfony/maker-bundle (Packagist) ECOSYSTEM:introduced=1.27.0,fixed=1.29.2; symfony/security (Packagist) ECOSYSTEM:introduced=5.0.0,fixed=5.2.8; symfony/security-core (Packagist) ECOSYSTEM:introduced=2.8.0,fixed=3.4.48; and 3 more.

**Is there a fix for CVE-2021-21424?** Yes. lexik/jwt-authentication-bundle (Packagist): upgrade to 2.10.7 or later; symfony/maker-bundle (Packagist): upgrade to 1.29.2 or later; symfony/security (Packagist): upgrade to 5.2.8 or later; symfony/security-core (Packagist): upgrade to 3.4.48 or later; symfony/security-guard (Packagist): upgrade to 3.4.48 or later; symfony/security-http (Packagist): upgrade to 5.2.8 or later; symfony/symfony (Packagist): upgrade to 3.4.49 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2021-21424?** Check whether you run lexik/jwt-authentication-bundle (Packagist), symfony/maker-bundle (Packagist), symfony/security (Packagist) or one of the others listed 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

- lexik/jwt-authentication-bundle (Packagist): upgrade to 2.10.7 or later

  ```sh
  composer require lexik/jwt-authentication-bundle:^2.10.7
  ```

- symfony/maker-bundle (Packagist): upgrade to 1.29.2 or later

  ```sh
  composer require symfony/maker-bundle:^1.29.2
  ```

- symfony/security (Packagist): upgrade to 5.2.8 or later

  ```sh
  composer require symfony/security:^5.2.8
  ```

- symfony/security-core (Packagist): upgrade to 3.4.48 or later

  ```sh
  composer require symfony/security-core:^3.4.48
  ```

- symfony/security-guard (Packagist): upgrade to 3.4.48 or later

  ```sh
  composer require symfony/security-guard:^3.4.48
  ```

- symfony/security-http (Packagist): upgrade to 5.2.8 or later

  ```sh
  composer require symfony/security-http:^5.2.8
  ```

- symfony/symfony (Packagist): upgrade to 3.4.49 or later

  ```sh
  composer require symfony/symfony:^3.4.49
  ```


## Affected products

- lexik/jwt-authentication-bundle (Packagist) ECOSYSTEM:introduced=2.0.0,fixed=2.10.7
- symfony/maker-bundle (Packagist) ECOSYSTEM:introduced=1.27.0,fixed=1.29.2
- symfony/security (Packagist) ECOSYSTEM:introduced=5.0.0,fixed=5.2.8
- symfony/security-core (Packagist) ECOSYSTEM:introduced=2.8.0,fixed=3.4.48
- symfony/security-guard (Packagist) ECOSYSTEM:introduced=2.8.0,fixed=3.4.48
- symfony/security-http (Packagist) ECOSYSTEM:introduced=5.1.0,fixed=5.2.8
- symfony/symfony (Packagist) ECOSYSTEM:introduced=2.8.0,fixed=3.4.49

## Identifiers

- CVE-2021-21424
- GHSA-5pv8-ppvj-4h68

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