CVE-2021-35955
MEDIUM
4.8
CVSS Score
Published: August 12, 2021 at 02:33 PM UTC
Updated: June 17, 2026 at 03:58 AM UTC
1 product affected across 1 vendorContao
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Severity
MEDIUM4.8
Exploit prediction
EPSS 0.6%
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.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
4.0.0 ≤ v < 4.4.564.10.0 ≤ v < 4.11.74.5.0 ≤ v < 4.9.18
Affected range stops below 4.11.7, so it looks safe — our inference, not a vendor statement
Affected range stops below 4.4.56, so it looks safe — our inference, not a vendor statement
Affected range stops below 4.9.18, so it looks safe — our inference, not a vendor statement
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
References (2)
x_refsource_MISCVendor Advisory
Source: [email protected]
https://contao.org/en/news/contao-4-9-16-and-4-11-5-are-available.htmlx_refsource_MISCThird Party Advisory
Source: [email protected]
https://github.com/contao/contao/security/advisories/GHSA-hr3h-x6gq-rqcpCVSS
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- HIGH
- User Interaction
- REQUIRED
- Scope
- CHANGED
- Confidentiality
- LOW
- Integrity
- LOW
- Availability
- NONE
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-79
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