CVE-2016-4423: debian debian_linux Resource Management Errors
Vulnerability summary
CVE-2016-4423 is a high (CVSS 7.5) Resource Management Errors vulnerability in debian debian_linux. EPSS estimates a 1.86% chance of exploitation in the next 30 days, higher than 78.9% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 1Timeline
- 01-06-2016PublishedVulnerability first disclosed.
- 06-08-2024Last modifiedVulnerability information updated.
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 metrics
4 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated7.5HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated7.5HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
1.86%
Chance of exploitation in the next 30 days
Percentile
79%
Versus all other CVEs
30-day change
0.00 pp
From 1.86% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Debian2 products
- symfony< 2.8.6+dfsg-1
- debian_linuxEOL8.0
Sensiolabs1 product
- symfonyEOL≤ 2.3.40 | 2.7.0 | 2.7.1 | 2.7.2 | 2.7.3 | 2.7.4 | 2.7.5 | 2.7.6 | 2.7.7 | 2.7.8 | 2.7.9 | 2.7.10 | 2.7.11 | 2.7.12 | 2.8.0 | 2.8.1 | 2.8.2 | 2.8.3 | 2.8.4 | 2.8.5 | 3.0.0 | 3.0.1 | 3.0.2 | 3.0.3 | 3.0.4 | 3.0.5
Ubuntu1 product
- symfonyAll versions (No fix recorded)
3 vendors · 4 products
References
6 links- symfony.com/blog/cve-2016-4423-large-username-storage-in-sessionX Refsource CONFIRMVendor AdvisoryREPORT
