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CVE-2021-21424

Prevent user enumeration using Guard or the new Authenticator-based Security

Published: May 13, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSA BDUCWE-200
NVD MITRE
5.3CVSSMEDIUM
EPSS Score
1.7%
Top 25.6%
CISA KEV
Not in KEV
Exploits
6 Known
Remediation
Patch Available

Description

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. The ability to enumerate users was possible without relevant permissions due to different handling depending on whether the user existed or not when attempting to use the switch users functionality. We now ensure that 403s are returned whether the user exists or not if a user cannot switch to a user or if the user does not exist. The patch for this issue is available for branch 3.4.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:LI:NA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:LConfidentiality
Low
I:NIntegrity
None
A:NAvailability
None
Open in CVSS calculator →

Weaknesses

CWE-200CWE-203

Affected Products

symfonysensiolabs
LibraryLibrary
OSS Libraries / generic-library
fedorafedoraproject
On-premOS
Operating Systems / linux-distro
symfonysymfony
Library
OSS Libraries / web-framework
FedoraFedora Project
On-premOS
Operating Systems / linux-distro
SymfonySensioLabs, symfony community
Library
OSS Libraries / web-framework
sensiolabsoss-projectOSS Libraries
fedoraprojectoss-projectUSOperating Systemsaka fedora project
symfonyoss-projectOSS Librariesaka symfony framework, twig (related)
fedora projectoss-projectUSOperating Systemsaka fedora
sensiolabs, symfony communityoss-projectFROSS Librariesaka symfony, twig
and 10 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

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Exploitability

6 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

MITRE ATT&CK

2 techniques
Collection
Discovery
View detailed technique mapping

References

https://github.com/symfony/symfony/commit/2a581d22cc621b33d5464ed65c4bc2057f72f011
github.com
https://github.com/symfony/symfony/security/advisories/GHSA-5pv8-ppvj-4h68
github.com
https://lists.debian.org/debian-lts-announce/2023/07/msg00014.html
lists.debian.org
and 31 more references View all →

Timeline

Published
May 13, 2021
Last Updated
Nov 21, 2024

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