CVE-2016-4423
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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.86%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 3.0
- 7.5 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 1.86% probability · 78th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-399
- Affected
- sensiolabs/symfony · debian/debian linux
- Source
- cve@mitre.org
References
- 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-sessionVendor Advisory
- 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-sessionVendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.