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CVE-2021-21370: Cross-Site Scripting in Content Preview (CType menu)

medium Affects typo3/cms, typo3/cms-backend, typo3/cms-core. Feed 2026.10.29.1, updated 2026-10-28; published ; advisory modified .

Cross-Site Scripting in Content Preview (CType menu)

Package
typo3/cms Composer
Affected versions
>=10.0.0 and <10.4.14 or >=11.0.0 and <11.1.1 or >=9.0.0 and <9.5.25
Fixed in
10.4.14, 11.1.1, 9.5.25
Severity
medium  CVSS 5.4
Exploitation
not on CISA KEV · EPSS 1% (58.7th percentile)
Published
2021-03-23
Source
osv.dev

References

Cross-Site Scripting in Content Preview (CType menu)

Package
typo3/cms-backend Composer
Affected versions
>=7.0.0 and <7.6.51 or >=8.0.0 and <8.7.40 or >=9.0.0 and <9.5.25 or >=10.0.0 and <10.4.14 or >=11.0.0 and <11.1.1
Fixed in
7.6.51, 8.7.40, 9.5.25, 10.4.14, 11.1.1
Severity
medium  CVSS 5.4
Exploitation
not on CISA KEV · EPSS 1% (58.7th percentile)
Published
2021-03-23
Source
osv.dev

References

Cross-Site Scripting in Content Preview (CType menu)

Package
typo3/cms-core Composer
Affected versions
>=10.0.0 and <10.4.14 or >=11.0.0 and <11.1.1 or >=9.0.0 and <9.5.25
Fixed in
10.4.14, 11.1.1, 9.5.25
Severity
medium  CVSS 5.4
Exploitation
not on CISA KEV · EPSS 1% (58.7th percentile)
Published
2021-03-23
Source
osv.dev

References

CWE-79
NVD recordtypo3/cms advisoriestypo3/cms-backend advisoriestypo3/cms-core advisories

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