Back to Database
Status published
Medium
CVE-2021-35955
Contao >=4.0.0 allows backend XSS via HTML attributes to an...
Vulnerability Description
Contao >=4.0.0 allows backend XSS via HTML attributes to an HTML field. Fixed in 4.4.56, 4.9.18, 4.11.7.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
THREAT MONITOR
Am I Vulnerable?
Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2021-35955
Credits & Attribution
No credits recorded in the NVD database.
References
More from contao
View All →CVE-2025-65961
Contao is vulnerable to cross-site scripting in templates
Low
3.3
CVE-2025-65960
Contao is vulnerable to remote code execution in template closures
Medium
6.6
CVE-2025-57759
Contao has improper privilege management for page and article fields
Medium
4.3
CVE-2025-57758
Contao has improper access control in the back end voters
Medium
4.3
CVE-2025-57757
Contao discloses information in the news module
Medium
5.3
Affected Vendor
contao
View all reports →Affected Software
contao
Vulnerable Versions:
4.0.0, 4.5.0, 4.10.0
Timeline
Official Publish:
August 12th, 2021
Last Modified:
August 4th, 2024
Added to House:
July 21st, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
Weaknesses (CWE)
No CWE data available
MITRE ATT&CK TTPs
No associated TTPs found for this vulnerability.