CVE-2021-21370
Cross-Site Scripting in Content Preview (CType menu)
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Cross-Site Scripting in Content Preview (CType menu)
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.
- Record
CVE-2021-21370- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2021-0723
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.
- Record
EUVD-2021-0723- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-x7hc-x7fm-f7qh
Cross-Site Scripting in Content Preview (CType menu)
Problem
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.
Solution
Update to TYPO3 versions 7.6.51, 8.7.40, 9.5.25, 10.4.14, 11.1.1 that fix the problem described.
Credits
Thanks to TYPO3 contributor Oliver Bartsch who reported and fixed the issue.
References
- Record
GHSA-x7hc-x7fm-f7qh- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2021-21370- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - CVSS 2.0
- 3.5 Low
AV:N/AC:M/Au:S/C:N/I:P/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
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.
- Record
CVE-2021-21370- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
OSVGHSA-x7hc-x7fm-f7qh
Cross-Site Scripting in Content Preview (CType menu)
Problem
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.
Solution
Update to TYPO3 versions 7.6.51, 8.7.40, 9.5.25, 10.4.14, 11.1.1 that fix the problem described.
Credits
Thanks to TYPO3 contributor Oliver Bartsch who reported and fixed the issue.
References
- Record
GHSA-x7hc-x7fm-f7qh- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSVBIT-typo3-2021-21370 No score
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.
- Record
BIT-typo3-2021-21370- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
typo3/cms-backendPackagist |
7.0.0 to 7.6.50 | 7.6.51 |
typo3/cms-backendPackagist |
8.0.0 to 8.7.39 | 8.7.40 |
typo3/cms-backendPackagist |
9.0.0 to 9.5.24 | 9.5.25 |
typo3/cms-backendPackagist |
10.0.0 to 10.4.13 | 10.4.14 |
typo3/cms-backendPackagist |
11.0.0 to 11.1.0 | 11.1.1 |
typo3/cms-corePackagist |
10.0.0 up to 10.4.14 | 10.4.14 |
typo3/cms-corePackagist |
11.0.0 up to 11.1.1 | 11.1.1 |
typo3/cms-corePackagist |
9.0.0 up to 9.5.25 | 9.5.25 |
typo3/cmsPackagist |
10.0.0 up to 10.4.14 | 10.4.14 |
typo3/cmsPackagist |
11.0.0 up to 11.1.1 | 11.1.1 |
Show 13 moreShow less
| Package | Affected | Fixed |
|---|---|---|
typo3/cmsPackagist |
9.0.0 up to 9.5.25 | 9.5.25 |
typo3Bitnami |
7.0.0 up to 7.6.51, 8.0.0 up to 8.7.40, 9.0.0 up to 9.5.25, 10.0.0 up to 10.4.14, 11.0.0 up to 11.1.1 | 7.6.518.7.409.5.2510.4.1411.1.1 |
typo3/cms-backendPackagist |
7.0.0 up to 7.6.51 | 7.6.51 |
typo3/cms-backendPackagist |
8.0.0 up to 8.7.40, plus listed versions v8.7.10v8.7.11v8.7.12v8.7.13v8.7.14 Show 21 moreShow lessv8.7.15v8.7.16v8.7.17v8.7.18v8.7.19v8.7.20v8.7.21v8.7.22v8.7.23v8.7.24v8.7.25v8.7.26v8.7.27v8.7.28v8.7.29v8.7.30v8.7.31v8.7.32v8.7.7v8.7.8v8.7.9 |
8.7.40 |
typo3/cms-backendPackagist |
9.0.0 up to 9.5.25, plus listed versions v9.0.0v9.1.0v9.2.0v9.2.1v9.3.0 Show 29 moreShow lessv9.3.1v9.3.2v9.3.3v9.4.0v9.5.0v9.5.1v9.5.10v9.5.11v9.5.12v9.5.13v9.5.14v9.5.15v9.5.16v9.5.17v9.5.18v9.5.19v9.5.2v9.5.20v9.5.21v9.5.22v9.5.23v9.5.24v9.5.3v9.5.4v9.5.5v9.5.6v9.5.7v9.5.8v9.5.9 |
9.5.25 |
typo3/cms-backendPackagist |
10.0.0 up to 10.4.14, plus listed versions v10.0.0v10.1.0v10.2.0v10.2.1v10.2.2 Show 15 moreShow lessv10.3.0v10.4.0v10.4.1v10.4.10v10.4.11v10.4.12v10.4.13v10.4.2v10.4.3v10.4.4v10.4.5v10.4.6v10.4.7v10.4.8v10.4.9 |
10.4.14 |
typo3/cms-backendPackagist |
11.0.0 up to 11.1.1, plus listed versions v11.0.0v11.1.0 |
11.1.1 |
typo3/cms-corePackagist |
10.0.0 up to 10.4.14, plus listed versions v10.0.0v10.1.0v10.2.0v10.2.1v10.2.2 Show 15 moreShow lessv10.3.0v10.4.0v10.4.1v10.4.10v10.4.11v10.4.12v10.4.13v10.4.2v10.4.3v10.4.4v10.4.5v10.4.6v10.4.7v10.4.8v10.4.9 |
10.4.14 |
typo3/cms-corePackagist |
11.0.0 up to 11.1.1, plus listed versions v11.0.0v11.1.0 |
11.1.1 |
typo3/cms-corePackagist |
9.0.0 up to 9.5.25, plus listed versions v9.0.0v9.1.0v9.2.0v9.2.1v9.3.0 Show 29 moreShow lessv9.3.1v9.3.2v9.3.3v9.4.0v9.5.0v9.5.1v9.5.10v9.5.11v9.5.12v9.5.13v9.5.14v9.5.15v9.5.16v9.5.17v9.5.18v9.5.19v9.5.2v9.5.20v9.5.21v9.5.22v9.5.23v9.5.24v9.5.3v9.5.4v9.5.5v9.5.6v9.5.7v9.5.8v9.5.9 |
9.5.25 |
typo3/cmsPackagist |
10.0.0 up to 10.4.14, plus listed versions v10.0.0v10.1.0v10.2.0v10.2.1v10.2.2 Show 15 moreShow lessv10.3.0v10.4.0v10.4.1v10.4.10v10.4.11v10.4.12v10.4.13v10.4.2v10.4.3v10.4.4v10.4.5v10.4.6v10.4.7v10.4.8v10.4.9 |
10.4.14 |
typo3/cmsPackagist |
11.0.0 up to 11.1.1, plus listed versions v11.0.0v11.1.0 |
11.1.1 |
typo3/cmsPackagist |
9.0.0 up to 9.5.25, plus listed versions v9.0.0v9.1.0v9.2.0v9.2.1v9.3.0 Show 29 moreShow lessv9.3.1v9.3.2v9.3.3v9.4.0v9.5.0v9.5.1v9.5.10v9.5.11v9.5.12v9.5.13v9.5.14v9.5.15v9.5.16v9.5.17v9.5.18v9.5.19v9.5.2v9.5.20v9.5.21v9.5.22v9.5.23v9.5.24v9.5.3v9.5.4v9.5.5v9.5.6v9.5.7v9.5.8v9.5.9 |
9.5.25 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-21370 is a medium vulnerability (CVSS 5.4) in Typo3, published March 23, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.87%, the 59th percentile. Fixed in typo3/cms-backend 7.6.51.
References
packagist.org/packages/typo3/cms-backend
github.com/TYPO3/TYPO3.CMS/security/advisories/GHSA-x7hc-x7fm-f7qh
typo3.org/security/advisory/typo3-core-sa-2021-008
nvd.nist.gov/vuln/detail/CVE-2021-21370