CVE-2021-21370 json
Cross-Site Scripting in Content Preview (CType menu)
published 2021-03-23 5 y ago modified 2026-07-08 4 mo ago also BIT-typo3-2021-21370 , EUVD-2021-0723 , GHSA-x7hc-x7fm-f7qh
- cvss
- 5.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 59%
- public exploits
- 0
- none known
Summary
TYPO3 is an open source PHP based web content management system. In TYPO3 before versions 7.6.51, 8.7.40, 9.5.25, 10.4.14, 11.1.1 it has been discovered that content elements of type _menu_ are vulnerable to cross-site scripting when their referenced items get previewed in the page module. A valid backend user account is needed to exploit this vulnerability. This is fixed in versions 7.6.51, 8.7.40, 9.5.25, 10.4.14, 11.1.1.
Patch / fix
- packagist typo3/cms-backend 7.6.51, 8.7.40, 9.5.25, 10.4.14, 11.1.1
- 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 7.6.51, 8.7.40, 9.5.25, 10.4.14, 11.1.1
- typo3 typo3 7.6.51, 8.7.40, 9.5.25, 10.4.14, 11.1.1
Exploit prediction
0.87% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| GitHub | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| NVD | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 3.5 | AV:N/AC:M/Au:S/C:N/I:P/A:N |
| OSV | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| packagist | typo3/cms-backend | >=7.0.0, <7.6.51 >=8.0.0, <8.7.40 >=9.0.0, <9.5.25 >=10.0.0, <10.4.14 >=11.0.0, <11.1.1 |
7.6.51 8.7.40 9.5.25 10.4.14 11.1.1 |
| 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 | >=7.0.0, <7.6.51 >=8.0.0, <8.7.40 >=9.0.0, <9.5.25 >=10.0.0, <10.4.14 >=11.0.0, <11.1.1 |
7.6.51 8.7.40 9.5.25 10.4.14 11.1.1 |
Affected products
- TYPO3 TYPO3.CMS
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
typo3.org
/security/advisory/typo3-core-sa-2021-008
web, vendor-advisory
-
packagist.org
/packages/typo3/cms-backend
web, release-notes, third-party-advisory
-
github.com
/TYPO3/TYPO3.CMS/security/advisories/GHSA-x7hc-x7fm-f7qh
web, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2021-21370
advisory
-
github.com
/FriendsOfPHP/security-advisories/blob/master/typo3/cms-core/CVE-2021-21370.yaml
web
-
github.com
/FriendsOfPHP/security-advisories/blob/master/typo3/cms/CVE-2021-21370.yaml
web
Sources
- CVE List CVE-2021-21370
- GitHub Advisory GHSA-x7hc-x7fm-f7qh
- NVD CVE-2021-21370
- OSV BIT-typo3-2021-21370
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