CVE-2021-21359 json
Denial of Service in Page Error Handling
published 2021-03-23 5 y ago modified 2026-07-08 4 mo ago also BIT-typo3-2021-21359 , EUVD-2021-0598 , GHSA-4p9g-qgx9-397p
- cvss
- 5.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.7%
- EPSS 1.7% chance of exploitation in 30 days, percentile 77%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- packagist typo3/cms-core 9.5.25, 10.4.14, 11.1.1
- packagist typo3/cms 9.5.25, 10.4.14, 11.1.1
- bitnami typo3 9.5.25, 10.4.14, 11.1.1
- typo3 typo3 9.5.25, 10.4.14, 11.1.1
Exploit prediction
1.73% chance of exploitation in the next 30 days, higher than 77% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H |
| GitHub | 3.1 | 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H/E:F/RL:O/RC:C |
| NVD | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVD | 2.0 | 5.0 | AV:N/AC:L/Au:N/C:N/I:N/A:P |
| OSV | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| packagist | typo3/cms-core | >=10.0.0, <10.4.14 >=11.0.0, <11.1.1 >=9.0.0, <9.5.25 |
10.4.14 11.1.1 9.5.25 |
| packagist | typo3/cms | >=10.0.0, <10.4.14 >=11.0.0, <11.1.1 >=9.0.0, <9.5.25 |
10.4.14 11.1.1 9.5.25 |
| bitnami | typo3 | >=9.0.0, <9.5.25 >=10.0.0, <10.4.14 >=11.0.0, <11.1.1 |
9.5.25 10.4.14 11.1.1 |
Affected products
- TYPO3 TYPO3.CMS
Classification
References
-
typo3.org
/security/advisory/typo3-core-sa-2021-005
web, vendor-advisory
-
packagist.org
/packages/typo3/cms-core
web, release-notes, third-party-advisory
-
github.com
/TYPO3/TYPO3.CMS/security/advisories/GHSA-4p9g-qgx9-397p
web, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2021-21359
advisory
-
github.com
/FriendsOfPHP/security-advisories/blob/master/typo3/cms-core/CVE-2021-21359.yaml
web
-
github.com
/FriendsOfPHP/security-advisories/blob/master/typo3/cms/CVE-2021-21359.yaml
web
Sources
- CVE List CVE-2021-21359
- GitHub Advisory GHSA-4p9g-qgx9-397p
- NVD CVE-2021-21359
- OSV BIT-typo3-2021-21359
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