CVE-2021-21424

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

Published May 13, 2021 CVSS 3.1 · 5.3 Medium EPSS 1.6% KEV · Not listed
Description
Symfony is a PHP framework for web and console applications and a set of reusable PHP components. The ability to enumerate users was possible without relevant permissions due to different handling depending on whether the user existed or not when attempting to use the switch users functionality. We now ensure that 403s are returned whether the user exists or not if a user cannot switch to a user or if the user does not exist. The patch for this issue is available for branch 3.4.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Debian DLA Debian DLA DLA-3493-1 symfony security update
EUVD EUVD EUVD-2021-0960 Symfony is a PHP framework for web and console applications and a set of reusable PHP components. The ability to enumerate users was possible without relevant permissions due to different handling depending on whether the user existed or not when attempting to use the switch users functionality. We now ensure that 403s are returned whether the user exists or not if a user cannot switch to a user or if the user does not exist. The patch for this issue is available for branch 3.4.
Github GHSA Github GHSA GHSA-5pv8-ppvj-4h68 Prevent user enumeration using Guard or the new Authenticator-based Security
Ubuntu USN Ubuntu USN USN-5290-1 Symfony vulnerabilities
History

No history.

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Aug 3, 2024, 6:09 PM
Reserved
Dec 22, 2020, 12:00 AM
Status
Modified
Published
May 13, 2021, 4:15 PM
Modified
Jun 17, 2026, 3:35 AM