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Fencer Intel
medium 5.4

CVE-2021-21370 json

Cross-Site Scripting in Content Preview (CType menu)

published 5y ago modified 4mo 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

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Exploit prediction

0.87% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-09).

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

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.