SB2021051228 - User enumeration in Symfony
Published: May 12, 2021 Updated: May 21, 2026
Security Bulletin ID
SB2021051228
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Information disclosure
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Observable response discrepancy (CVE-ID: CVE-2021-21424)
CWE-ID: CWE-204 - Observable Response Discrepancy
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a remote attacker to enumerate application users.
The vulnerability exists due to application returns different responses based on presence of user account name in application database. A remote attacker enumerate application users.
Remediation
Install update from vendor's website.