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CVE-2021-35955: Cross site scripting via HTML attributes in the back end

medium Affects contao/contao, contao/core-bundle. Feed 2026.10.29.1, updated 2026-10-28; published ; advisory modified .

Cross site scripting via HTML attributes in the back end

Package
contao/contao Composer
Affected versions
>=4.0.0 and <4.4.56 or >=4.5.0 and <4.9.18 or >=4.10.0 and <4.11.7 or >=4.5.0 and <4.6.0 or >=4.6.0 and <4.7.0 or >=4.7.0 and <4.8.0 or >=4.8.0 and <4.9.0 or >=4.9.0 and <4.9.18 or >=4.10.0 and <4.11.0 or >=4.11.0 and <4.11.7
Fixed in
4.4.56, 4.9.18, 4.11.7
Severity
medium  CVSS 5.9
Exploitation
not on CISA KEV · EPSS 1% (46.4th percentile)
Published
2021-08-25
Source
osv.dev

References

Cross site scripting via HTML attributes in the back end

Package
contao/core-bundle Composer
Affected versions
>=4.0.0 and <4.4.56 or >=4.5.0 and <4.9.18 or >=4.10.0 and <4.11.7 or >=4.5.0 and <4.6.0 or >=4.6.0 and <4.7.0 or >=4.7.0 and <4.8.0 or >=4.8.0 and <4.9.0 or >=4.9.0 and <4.9.18 or >=4.10.0 and <4.11.0 or >=4.11.0 and <4.11.7
Fixed in
4.4.56, 4.9.18, 4.11.7
Severity
medium  CVSS 5.9
Exploitation
not on CISA KEV · EPSS 1% (46.4th percentile)
Published
2021-08-25
Source
osv.dev

References

CWE-79
NVD recordcontao/contao advisoriescontao/core-bundle advisories

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