CVE-2021-21359
Published:March 23, 2021
Updated:May 17, 2026
TYPO3 is an open source PHP based web content management system. In TYPO3 before versions 9.5.25, 10.4.14, 11.1.1 requesting invalid or non-existing resources via HTTP triggers the page error handler which again could retrieve content to be shown as error message from another page. This leads to a scenario in which the application is calling itself recursively - amplifying the impact of the initial attack until the limits of the web server are exceeded. This is fixed in versions 9.5.25, 10.4.14, 11.1.1.
Affected Packages
typo3/cms-core (PHP):
Affected version(s) >=v11.0.0 <v11.1.1Fix Suggestion:
Update to version v11.1.1typo3/cms-core (PHP):
Affected version(s) >=v10.0.0 <v10.4.14Fix Suggestion:
Update to version v10.4.14typo3/cms-core (PHP):
Affected version(s) >=v9.0.0 <v9.5.25Fix Suggestion:
Update to version v9.5.25Related Resources (6)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.2
Attack Vector
NETWORK
Attack Complexity
HIGH
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
Exploit Maturity
POC
CVSS v3
Base Score:
5.9
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Exploit Maturity
FUNCTIONAL
Weakness Type (CWE)
EPSS
Base Score:
0.30