VULNERABILITY INTELLIGENCE
CVE-2016-4423
CVSS score7.5 HIGH
EPSS probability1.86%
CISA KEVNot currently listed
Published2016-06-01
Last modified2026-06-17
CVSS vectorCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Description
The attemptAuthentication function in Component/Security/Http/Firewall/UsernamePasswordFormAuthenticationListener.php in Symfony before 2.3.41, 2.7.x before 2.7.13, 2.8.x before 2.8.6, and 3.0.x before 3.0.6 does not limit the length of a username stored in a session, which allows remote attackers to cause a denial of service (session storage consumption) via a series of authentication attempts with long, non-existent usernames.