CVE-2016-4423 Information

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.

CVSS Vector

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Reference

http://www.debian.org/security/2016/dsa-3588 https://github.com/symfony/symfony/pull/18733 https://symfony.com/blog/cve-2016-4423-large-username-storage-in-session

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

NONE

Base Score

HIGH

Base Severity

7.5