CVE-2021-21359 - CVE House
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Status published Medium CVE-2021-21359

Denial of Service in Page Error Handling

Vulnerability Description

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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

TYPO3.CMS
Vulnerable Versions:
>= 9.0.0, <= 9.5.24, >= 10.0.0, <= 10.4.13, >= 11.0.0, <= 11.1.0

Timeline

Official Publish: March 23rd, 2021
Last Modified: August 3rd, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

CWE-674 CWE-405

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.